<PAGE>   1
                                                                  Exhibit 10.40


                           REVOLVING CREDIT AGREEMENT
                           --------------------------



                          DATED as of January 8, 1997




                                      among



                                HADCO CORPORATION



                                       and




                       THE FIRST NATIONAL BANK OF BOSTON,
                           Individually and as Agent,

                                       and

                         THE OTHER LENDING INSTITUTIONS
                           LISTED ON SCHEDULE 1 HERETO
                                     -------- - ------


<PAGE>   2

<TABLE>

                                             TABLE OF CONTENTS
                                             -----------------


<S> <C>                                                                                              <C>
1.  DEFINITIONS AND RULES OF INTERPRETATION.  .....................................................  1
         1.1.  Definitions.  ......................................................................  1
         1.2.  Rules of Interpretation.  ..........................................................  14
2.  THE REVOLVING CREDIT FACILITY.  ...............................................................  15
         2.1.  Commitment to Lend.  ...............................................................  15
         2.2.  Commitment Fee.  ...................................................................  15
         2.3.  Reduction of Total Commitment.  ....................................................  15
         2.4.  The Notes.  ........................................................................  16
         2.5.  Interest on Loans.  ................................................................  17
         2.6.  Requests for Loans.  ...............................................................  17
         2.7.  Conversion Options.  ...............................................................  17
                  2.7.1.  Conversion to Different Type of Loan.  ..................................  17
                  2.7.2.  Continuation of Type of Loan.  ..........................................  18
                  2.7.3.  Eurodollar Rate Loans.  .................................................  18
         2.8.  Funds for Loans.  ..................................................................  18
                  2.8.1.  Funding Procedures.  ....................................................  18
                  2.8.2.  Advances by Agent.  .....................................................  19
3.  REPAYMENT OF THE REVOLVING CREDIT LOANS.  .....................................................  19
         3.1.  Maturity.  .........................................................................  19
         3.3.  Optional Repayments of Loans.  .....................................................  20
4.  LETTERS OF CREDIT.  ...........................................................................  20
         4.1.  Letter of Credit Commitments........................................................  20
                  4.1.1.  Commitment to Issue Letters of Credit.  .................................  20
                  4.1.2.  Letter of Credit Applications.  .........................................  21
                  4.1.3.  Terms of Letters of Credit.  ............................................  21
                  4.1.4.  Reimbursement Obligations of Banks.  ....................................  21
                  4.1.5.  Participations of Banks.  ...............................................  21
         4.2.  Reimbursement Obligation of the Borrower.  .........................................  21
         4.3.  Letter of Credit Payments.  ........................................................  22
         4.4.  Obligations Absolute.  .............................................................  23
         4.5.  Reliance by Issuer.  ...............................................................  23
         4.6.  Letter of Credit Fee.  .............................................................  24
5.  CERTAIN GENERAL PROVISIONS.  ..................................................................  24
         5.1.  Fees.  .............................................................................  24
         5.2.  Funds for Payments.  ...............................................................  24
                  5.2.1.  Payments to Agent.  .....................................................  24
                  5.2.2.  No Offset, etc.  ........................................................  24
         5.3.  Computations.  .....................................................................  25
         5.4.  Inability to Determine Eurodollar Rate.  ...........................................  25
         5.5.  Illegality.  .......................................................................  26
         5.6.  Additional Costs, etc.  ............................................................  26
         5.7.  Capital Adequacy.  .................................................................  27
</TABLE>

<PAGE>   3

                                      -ii-


<TABLE>

<S> <C>                                                                                              <C>
         5.8.   Certificate.  .....................................................................  28
         5.9.   Indemnity.  .......................................................................  28
         5.10.  Interest After Default.  ..........................................................  28
                  5.10.1.  Overdue Amounts.  ......................................................  28
                  5.10.2.  Amounts Not Overdue.  ..................................................  28
6.  GUARANTIES AND PLEDGE OF SECURITIES.  .........................................................  28
7.  REPRESENTATIONS AND WARRANTIES.  ..............................................................  29
         7.1.   Corporate Authority.  .............................................................  29
                  7.1.1.  Incorporation; Good Standing.  ..........................................  29
                  7.1.2.  Authorization.  .........................................................  29
                  7.1.3.  Enforceability.  ........................................................  29
         7.2.   Governmental Approvals.  ..........................................................  30
         7.3.   Title to Properties; Leases.  .....................................................  30
         7.4.   Financial Statements, Projections, Pro Forma Balance Sheet and Solvency.  .........  30
                  7.4.1.  Financial Statements.  ..................................................  30
                  7.4.2.  Projections.  ...........................................................  31
                  7.4.3.  Pro Forma Balance Sheet.  ...............................................  31
                  7.4.4.  Solvency.  ..............................................................  31
         7.5.   No Material Changes, etc.  ........................................................  32
         7.6.   Franchises, Patents, Copyrights, etc.  ............................................  32
         7.7.   Litigation.  ......................................................................  32
         7.8.   No Materially Adverse Contracts, etc.  ............................................  32
         7.9.   Compliance with Other Instruments, Laws, etc.  ....................................  33
         7.10.  Tax Status.  ......................................................................  33
         7.11.  No Event of Default.  .............................................................  33
         7.12.  Holding Company and Investment Company Acts.  .....................................  33
         7.13.  Absence of Financing Statements; Perfection of Security Interest.  ................  33
         7.14.  Certain Transactions.  ............................................................  34
         7.15.  Employee Benefit Plans.  ..........................................................  34
                  7.15.1.  In General.  ...........................................................  34
                  7.15.2.  Terminability of Welfare Plans.  .......................................  34
                  7.15.3.  Guaranteed Pension Plans.  .............................................  34
                  7.15.4.  Multiemployer Plans.  ..................................................  35
         7.16.  Use of Proceeds.  .................................................................  35
         7.17.  Environmental Compliance.  ........................................................  35
         7.18.  Subsidiaries, etc.  ...............................................................  37
         7.19.  Merger and Tender Offer.  .........................................................  37
         7.20.  Disclosure.  ......................................................................  38
8.  AFFIRMATIVE COVENANTS OF THE BORROWER.  .......................................................  38
         8.1.   Punctual Payment.  ................................................................  38
         8.2.   Maintenance of Office.  ...........................................................  38
         8.3.   Records and Accounts.  ............................................................  38
         8.4.   Financial Statements, Certificates and Information.  ..............................  38
</TABLE>


<PAGE>   4


                                     -iii-

<TABLE>

<S>  <C>                                                                                             <C>
         8.5.   Notices.  .........................................................................  40
                  8.5.1.  Defaults.  ..............................................................  40
                  8.5.2.  Environmental Events.  ..................................................  40
                  8.5.3.  Notice of Litigation and Judgments.  ....................................  40
                  8.5.4.  Notification of Claims Against Securities.  .............................  41
         8.6.   Corporate Existence; Maintenance of Properties.  ..................................  41
         8.7.   Insurance.  .......................................................................  41
         8.8.   Taxes.  ...........................................................................  42
         8.9.   Inspection of Properties and Books, etc.  .........................................  42
                  8.9.1.  General.  ...............................................................  42
                  8.9.2.  Communications with Accountants.  .......................................  42
         8.10.  Compliance with Laws, Contracts, Licenses, and Permits.  ..........................  42
         8.11.  Employee Benefit Plans.  ..........................................................  43
         8.12.  Use of Proceeds.  .................................................................  43
         8.13.  Interest Rate Protection Agreements.  .............................................  43
         8.14.  Confirmation of Guaranty; Additional Guaranties.  .................................  43
         8.15.  Consummation of Merger.  ..........................................................  44
         8.16.  Delivery of Securities.  ..........................................................  44
         8.17.  Further Assurances.  ..............................................................  44
         8.18.  Post-Closing Undertakings.  .......................................................  44
9.   CERTAIN NEGATIVE COVENANTS OF THE BORROWER.  .................................................  44
         9.1.   Restrictions on Indebtedness.  ....................................................  44
         9.2.   Restrictions on Liens.  ...........................................................  47
         9.3.   Restrictions on Investments.  .....................................................  48
         9.4.   Distributions.  ...................................................................  49
         9.5.   Mergers and Consolidations, Acquisitions and Disposition of Assets.  ..............  50
                  9.5.1.  Mergers and Consolidations.  ............................................  50
                  9.5.2.  Acquisitions.  ..........................................................  50
                  9.5.3.  Disposition of Assets.  .................................................  51
         9.6.   Sale and Leaseback.  ..............................................................  51
         9.7.   Compliance with Environmental Laws.  ..............................................  51
         9.8.   Employee Benefit Plans.  ..........................................................  52
         9.9.   Changes to Transaction Documents.  ................................................  52
         9.10.  Capitalization.  ..................................................................  52
         9.11.  Agreements Regarding Hadco FSC.  ..................................................  53
10.  FINANCIAL COVENANTS OF THE BORROWER.  ........................................................  53
         10.1.  Funded Debt to EBITDA.  ...........................................................  53
         10.2.  Capital Expenditures.  ............................................................  53
         10.3.  Debt Service.  ....................................................................  54
         10.4.  Adjusted Consolidated Net Worth.  .................................................  54
11.  CLOSING CONDITIONS.  .........................................................................  54
         11.1.  Loan Documents; Transaction Documents.  ...........................................  54
                  11.1.1.  Loan Documents.  .......................................................  54
</TABLE>


<PAGE>   5
                                      -iv-


<TABLE>


<S>  <C>                                                                                             <C>
                  11.1.2.  Transaction Documents.  ................................................  55
         11.2.   Certified Copies of Charter Documents.  ..........................................  55
         11.3.   Corporate Action.  ...............................................................  55
         11.4.   Incumbency Certificate.  .........................................................  55
         11.5.   Validity of Liens; UCC Search Results.  ..........................................  55
                  11.5.1.  Validity of Liens.  ....................................................  55
                  11.5.2.  UCC Search Results.  ...................................................  55
         11.6.   Certificates of Insurance.  ......................................................  55
         11.7.   Form U-1.  .......................................................................  56
         11.8.   Solvency Certificate.  ...........................................................  56
         11.9.   Opinion of Counsel.  .............................................................  56
         11.10.  Payment of Fees.  ................................................................  56
         11.11.  Tender Offer.  ...................................................................  56
                  11.11.1.  Adequate Tender of Securities.  .......................................  56
                  11.11.2.  Consummation of Tender Offer.  ........................................  56
         11.12.  Unused Debt Capacity.  ...........................................................  56
         11.13.  Payment of Existing Indebtedness; Consent of Other Lenders.  .....................  57
                  11.13.1.  Indebtedness of the Borrower To FNBB.  ................................  57
                  11.13.2.  Indebtedness of Zycon to Comerica Bank - California.  .................  57
                  11.13.3.  Consent of Equipment Lessors.  ........................................  57
                  11.13.4.  New York Urban Development Corporation.  ..............................  57
                  11.13.5.  Notice to Bank Bumiputra.  ............................................  57
         11.14.  Post-Closing Undertakings.  ......................................................  57
12.  CONDITIONS TO ALL BORROWINGS.  ...............................................................  58
         12.1.   Representations True; No Event of Default.  ......................................  58
         12.2.   No Legal Impediment.  ............................................................  58
         12.3.   Governmental Regulation.  ........................................................  58
         12.4.   Proceedings and Documents.  ......................................................  58
13.  EVENTS OF DEFAULT; ACCELERATION; ETC.  .......................................................  58
         13.1.   Events of Default and Acceleration.  .............................................  58
         13.2.   Termination of Commitments.  .....................................................  62
         13.3.   Remedies.  .......................................................................  62
14.  SETOFF.  .....................................................................................  63
15.  THE AGENT.  ..................................................................................  63
         15.1.   Authorization.  ..................................................................  63
         15.2.   Employees and Agents.  ...........................................................  64
         15.3.   No Liability.  ...................................................................  64
         15.4.   No Representations.  .............................................................  64
         15.5.   Payments.  .......................................................................  65
                  15.5.1.  Payments to Agent.  ....................................................  65
                  15.5.2.  Distribution by Agent.  ................................................  65
                  15.5.3.  Delinquent Banks.  .....................................................  65
         15.6.   Holders of Notes.  ...............................................................  66
</TABLE>


<PAGE>   6

                                      -v-

<TABLE>

<S>  <C>                                                                                             <C>
         15.7.  Indemnity.  .......................................................................  66
         15.8.  Agent as Bank.  ...................................................................  66
         15.9.  Resignation.  .....................................................................  66
16.  EXPENSES.  ...................................................................................  67
17.  INDEMNIFICATION.  ............................................................................  67
18.  SURVIVAL OF COVENANTS, ETC.  .................................................................  68
19.  ASSIGNMENT AND PARTICIPATION.  ...............................................................  69
         19.1.  Conditions to Assignment by Banks.  ...............................................  69
         19.2.  Certain Representations and Warranties; Limitations; Covenants.  ..................  69
         19.3.  Register.  ........................................................................  70
         19.4.  New Notes.  .......................................................................  71
         19.5.  Participations.  ..................................................................  71
         19.6.  Disclosure.  ......................................................................  71
         19.7.  Assignee or Participant Affiliated with the Borrower.  ............................  72
         19.8.  Miscellaneous Assignment Provisions.  .............................................  72
         19.9.  Assignment by Borrower.  ..........................................................  73
20.  NOTICES, ETC.  ...............................................................................  73
21.  GOVERNING LAW.  ..............................................................................  73
22.  HEADINGS.  ...................................................................................  74
23.  COUNTERPARTS.  ...............................................................................  74
24.  ENTIRE AGREEMENT, ETC.  ......................................................................  74
25.  WAIVER OF JURY TRIAL.  .......................................................................  74
26.  CONSENTS, AMENDMENTS, WAIVERS, ETC.  .........................................................  75
27.  SEVERABILITY.  ...............................................................................  75
28.  CONFIDENTIALITY...............................................................................  75

</TABLE>


<PAGE>   7


                                      -vi-


EXHIBITS
--------


Exhibit A                  -        Note
------- -
Exhibit B                  -        Loan Request
------- -
Exhibit C                  -        Compliance Certificate
------- -
Exhibit D                  -        Assignment and Acceptance
------- -
Exhibit E-1                -        Guaranty
------- ---
Exhibit E-2                -        Guaranty of Hadco Acquisition
------- ---
Exhibit F                  -        Stock Pledge Agreement
------- -

SCHEDULES
---------

Schedule 1                 -        Banks; Commitments
-------- -
Schedule 7.3               -        Title to Properties; Leases
-------- ---
Schedule 7.5               -        Contracts
-------- ---
Schedule 7.7               -        Litigation
-------- ---
Schedule 7.10              -        Tax Status
-------- ----
Schedule 7.17              -        Environmental Matters
-------- ----
Schedule 7.18              -        Subsidiaries
-------- ----
Schedule 7.19              -        Merger Documents and Tender Offer Documents
-------- ----
Schedule 8.18              -        Post-Closing Undertakings
-------- ----
Schedule 9.1               -        Indebtedness
-------- ---
Schedule 9.2               -        Liens
-------- ---
Schedule 9.3               -        Investments
-------- ---



<PAGE>   8




                           REVOLVING CREDIT AGREEMENT
                           --------------------------

     This REVOLVING CREDIT AGREEMENT is made as of January 8, 1997, by and
among HADCO CORPORATION (the "Borrower"), a Massachusetts corporation having its
principal place of business at 12A Manor Parkway, Salem, New Hampshire 03709,
and THE FIRST NATIONAL BANK OF BOSTON, a national banking association and the
other lending institutions listed on SCHEDULE 1 hereto, and THE FIRST NATIONAL
BANK OF BOSTON, as agent for itself and such other lending institutions.

                   1. DEFINITIONS AND RULES OF INTERPRETATION.
                      ---------------------------------------

     1.1 DEFINITIONS. The following terms shall have the meanings set forth in
this [Section]1 or elsewhere in the provisions of this Credit Agreement referred
to below:

     ACQUISITION RELATED WRITE-OFF. Up to $80,000,000 in non-cash expenses
associated with the purchase of goodwill of Zycon and with research and
development costs of Zycon.

     AFFILIATE. Any Person that would be considered to be an affiliate of the
Borrower under Rule 144(a) of the Rules and Regulations of the Securities and
Exchange Commission, as in effect on the date hereof, if the Borrower were
issuing securities.

     AGENT. The First National Bank of Boston, acting as agent for the Banks.

     AGENT'S HEAD OFFICE. The Agent's head office located at 100 Federal Street,
Boston, Massachusetts 02110, or at such other location as the Agent may
designate from time to time.

     AGENT'S SIDE LETTER. See [Section]5.2.

     AGENT'S SPECIAL COUNSEL. Bingham, Dana & Gould LLP or such other counsel as
may be approved by the Agent.

     APPLICABLE COMMITMENT FEE PERCENTAGE. For any fiscal quarter or portion
thereof, three-eighths of one percent (0.375%) per annum; PROVIDED, HOWEVER,
that in the event that the ratio of Funded Debt (calculated as of the last day
of such fiscal quarter or portion thereof) to EBITDA (calculated for the four
consecutive fiscal quarters ending on the last day of such fiscal quarter or
portion thereof) meets the requirements set forth in the chart below, the
Applicable Commitment Fee Percentage shall, commencing with the date which is
ten (10) days after any date on which the Borrower delivers to the Banks the
financial statements referred to in [Section]8.4(a) or (b) for such fiscal
quarter or portion

<PAGE>   9


                                      -2-

thereof and ending with the date nine (9) days after the next date on which the
Borrower delivers to each of the Banks the financial statements referred to in
[Section]8.4(a) or (b), be the percentage set forth opposite the applicable
ratio of Funded Debt to EBITDA in the table below:

     Ratio of Funded Debt                         Applicable Commitment Fee
          to EBITDA                                     Percentage
          ---------                                     ----------

Greater than or equal to 2.5:1.0                          0.375%
Greater than or equal to 2.0:1.0                          0.275%
  but less than 2.5:1.0
Greater than or equal to 1.5:1.0                          0.225%
  but less than 2.0:1.0
Less than 1.5:1.0                                         0.200%


     APPLICABLE EURODOLLAR RATE MARGIN. For any fiscal quarter or portion
thereof within any Interest Period with respect to any Eurodollar Rate Loan, one
and one-eighth percent (1.125%) per annum; PROVIDED, HOWEVER, that in the event
that the ratio of Funded Debt (calculated as of the last day of such fiscal
quarter or portion thereof) to EBITDA (calculated for the four consecutive
fiscal quarters ending on the last day of such fiscal quarter or portion
thereof) meets the requirements set forth in the chart below, the Applicable
Eurodollar Rate Margin shall, commencing with (but not before) the date which is
ten (10) days after the date on which the Borrower delivers to the Banks the
financial statements referred to in [Section]8.4(a) or (b) for such fiscal
quarter or portion thereof and ending with the date which is nine (9) days after
the next date on which the Borrower delivers to each of the Banks the financial
statements referred to in [Section]8.4(a) or (b), be the percentage set forth
opposite the applicable ratio of Funded Debt to EBITDA in the table below:

     Ratio of Funded Debt                           Applicable Eurodollar
          to EBITDA                                      Rate Margin
          ---------                                      -----------

Greater than or equal to 2.5:1.0                            1.125%
Greater than or equal to 2.0:1.0                            0.875%
  but less than 2.5:1.0
Greater than or equal to 1.5:10                             0.625%
  but less than 2.0:1.0
Less than 1.5:1.0                                           0.500%


     ASSIGNMENT AND ACCEPTANCE. See [Section]20.1.

     BALANCE SHEET DATE. October 26, 1996.

<PAGE>   10


                                      -3-


     BANK BUMIPUTRA LOAN AGREEMENT. The Loan Agreement dated as of February 9,
1996 among Zycon Corp. SDN BHD, Bank Bumiputra and certain other lenders, as in
effect on the date hereof.

     BANKS. FNBB and the other lending institutions listed on SCHEDULE 1 hereto
and any other Person who becomes an assignee of any rights and obligations of a
Bank pursuant to [Section]19.

     BASE RATE. The higher of (i) the annual rate of interest announced from
time to time by FNBB at its head office in Boston, Massachusetts, as its "base
rate" and (ii) one-half of one percent (1/2%) above the Federal Funds Effective
Rate. For the purposes of this definition, "Federal Funds Effective Rate" shall
mean for any day, the rate per annum equal to the weighted average of the rates
on overnight federal funds transactions with members of the Federal Reserve
System arranged by federal funds brokers, as published for such day (or, if such
day is not a Business Day, for the next preceding Business Day) by the Federal
Reserve Bank of New York, or, if such rate is not so published for any day that
is a Business Day, the average of the quotations for such day on such
transactions received by the Agent from three funds brokers of recognized
standing selected by the Agent.

     BASE RATE LOANS. Loans bearing interest calculated by reference to the Base
Rate.

     BORROWER. As defined in the preamble hereto.

     BUSINESS DAY. Any day on which banking institutions in Boston,
Massachusetts, are open for the transaction of banking business and, in the case
of Eurodollar Rate Loans, also a day which is a Eurodollar Business Day.

     CAPITAL ASSETS. Fixed assets, both tangible (such as land, buildings,
fixtures, machinery and equipment) and intangible (such as patents, copyrights,
trademarks, franchises and good will); PROVIDED that Capital Assets shall not
include any item customarily charged directly to expense or depreciated over a
useful life of twelve (12) months or less in accordance with generally accepted
accounting principles.

     CAPITAL EXPENDITURES. Amounts paid or indebtedness incurred by any of the
Transaction Parties in connection with the purchase or lease by any of the
Transaction Parties of Capital Assets that would be required to be capitalized
and shown on the balance sheet of such Person in accordance with generally
accepted accounting principles.

     CAPITALIZED LEASES. Leases under which any of the Transaction Parties is
the lessee or obligor, the discounted future rental payment obligations under
which are required to be capitalized on the balance sheet of the lessee or
obligor in accordance with generally accepted accounting principles.

<PAGE>   11


                                      -4-


     CERCLA. See [Section]7.18.

     CLOSING DATE. The first date on which the conditions set forth in
[Section]12 have been satisfied and any Loans are to be made or any Letter of
Credit is to be issued hereunder.

     CODE. The Internal Revenue Code of 1986, as amended and in effect from time
to time.

     COMMITMENT. With respect to each Bank, the amount set forth on SCHEDULE 1
hereto as the amount of such Bank's commitment to make Loans to, and to
participate in the issuance, extension and renewal of Letters of Credit for the
account of, the Borrower, as the same may be reduced from time to time; or if
such commitment is terminated pursuant to the provisions hereof, zero.

     COMMITMENT PERCENTAGE. With respect to each Bank, the percentage set forth
on SCHEDULE 1 hereto as such Bank's percentage of the aggregate Commitments of
all of the Banks.

     CONSOLIDATED OR CONSOLIDATED. With reference to any term defined herein,
shall mean that term as applied to the accounts of the Transaction Parties,
consolidated in accordance with generally accepted accounting principles.

     CONSOLIDATED FUNDED DEBT. At any time of determination, the sum of (i) the
amount of the Loans outstanding (after giving account to any amounts requested)
PLUS accrued but unpaid interest thereon; PLUS (ii) the Maximum Drawing Amount
and all Unpaid Reimbursement Obligations PLUS accrued but unpaid interest (if
any) thereon; PLUS (iii) the outstanding amount of any other Indebtedness for
borrowed money, in respect of Capitalized Leases or which is otherwise subject
to the payment of interest PLUS accrued but unpaid interest on such
Indebtedness, whether such interest was or is required to be reflected as an
item of expense or capitalized, including payments consisting of interest in
respect of Capitalized Leases and including commitment fees, agency fees,
facility fees, balance deficiency fees and similar fees or expenses in
connection with the borrowing of money.

     CONSOLIDATED NET INCOME (OR DEFICIT). The consolidated net income (or
deficit) of the Transaction Parties, after deduction of all expenses, taxes, and
other proper charges, determined in accordance with generally accepted
accounting principles, after eliminating therefrom all extraordinary
nonrecurring items of income and the Acquisition Related Write-off.

     CONSOLIDATED NET WORTH. The excess of Consolidated Total Assets over
Consolidated Total Liabilities.

     CONSOLIDATED TANGIBLE NET WORTH. The excess of Consolidated Total Assets
over Consolidated Total Liabilities, and less the sum of:

          (a) the total book value of all assets of the Transaction Parties
     properly classified as intangible assets under generally accepted

<PAGE>   12


                                      -5-


     accounting principles, including such items as good will, the purchase
     price of acquired assets in excess of the fair market value thereof,
     trademarks, trade names, service marks, brand names, copyrights, patents
     and licenses, and rights with respect to the foregoing; PLUS

          (b) all amounts representing any write-up in the book value of any
     assets of the Transaction Parties resulting from a revaluation thereof
     subsequent to the Balance Sheet Date, excluding adjustments to translate
     foreign assets and liabilities for changes in foreign exchange rates made
     in accordance with Financial Accounting Standards Board Statement No. 52;
     PLUS

          (c) to the extent otherwise includable in the computation of
     Consolidated Tangible Net Worth, any subscriptions receivable.

     CONSOLIDATED TOTAL ASSETS. All assets of the Transaction Parties determined
on a consolidated basis in accordance with generally accepted accounting
principles.

     CONSOLIDATED TOTAL INTEREST EXPENSE. For any period, the aggregate amount
of interest required to be paid or accrued by the Transaction Parties during
such period on all Indebtedness of the Transaction Parties outstanding during
all or any part of such period, whether such interest was or is required to be
reflected as an item of expense or capitalized, including payments consisting of
interest in respect of Capitalized Leases and including commitment fees, agency
fees, facility fees, balance deficiency fees and similar fees or expenses in
connection with the borrowing of money.

     CONSOLIDATED TOTAL LIABILITIES. All liabilities of the Transaction Parties
determined on a consolidated basis in accordance with generally accepted
accounting principles and all Indebtedness of the Transaction Parties, whether
or not so classified.

     CONVERSION REQUEST. A notice given by the Borrower to the Agent of the
Borrower's election to convert or continue a Loan in accordance with
[Section]2.7.

     CREDIT AGREEMENT. This Revolving Credit Agreement, including the Schedules
and Exhibits hereto.

     DEFAULT. See [Section]13.1.

     DISTRIBUTION. The declaration or payment of any dividend on or in respect
of any shares of any class of capital stock of the Borrower or, as the case may
be, Zycon, other than dividends payable solely in shares of common stock of the
Borrower or, as the case may be, Zycon, the purchase, redemption, or other
retirement of any shares of any class of capital stock, or any rights or options
convertible into shares of any class of capital stock, of the Borrower or, as
the case may be, Zycon, directly or indirectly through a Subsidiary of the
Borrower or, as the case may be, Zycon, or otherwise; the return of capital by
the Borrower 

<PAGE>   13

                                      -6-


or, as the case may be, Zycon, to its shareholders as such; or any other
distribution on or in respect of any shares of any class of capital stock of the
Borrower or, as the case may be, Zycon.

     DOLLARS or $. Dollars in lawful currency of the United States of America.

     DOMESTIC LENDING OFFICE. Initially, the office of each Bank designated as
such in SCHEDULE 1 hereto; thereafter, such other office of such Bank, if any,
located within the United States that will be making or maintaining Base Rate
Loans.

     DRAWDOWN DATE. The date on which any Loan is made or is to be made, and the
date on which any Loan is converted or continued in accordance with
[Section]2.7.

     EARNINGS BEFORE INTEREST AND TAXES or EBIT. The consolidated earnings (or
loss) from the operations of the Transaction Parties for any period, after all
expenses and other proper charges but before payment or provision for any income
taxes or interest expense, for such period, determined in accordance with
generally accepted account principles, after eliminating therefrom all
extraordinary nonrecurring items of income or loss, earnings from discontinued
businesses, any non-cash gains used in determining income and the Acquisition
Related Write-off.

     EARNINGS BEFORE INTEREST, TAXES, DEPRECIATION AND AMORTIZATION or EBITDA.
The consolidated earnings (or loss) from the operations of the Transaction
Parties for any period, after all expenses and other proper charges but before
payment or provision for any income taxes, interest expense, depreciation or
amortization for such period, determined in accordance with generally accepted
accounting principles, after eliminating therefrom all extraordinary
nonrecurring items of income or loss, earnings from discontinued businesses, any
non-cash gains used in determining income and the Acquisition Related Write-off.

     ELIGIBLE ASSIGNEE. Any of (i) a commercial bank or finance company
organized under the laws of the United States, or any State thereof or the
District of Columbia, and having total assets in excess of $1,000,000,000; (ii)
a savings and loan association or savings bank organized under the laws of the
United States, or any State thereof or the District of Columbia, and having a
net worth of at least $100,000,000, calculated in accordance with generally
accepted accounting principles; (iii) a commercial bank organized under the laws
of any other country which is a member of the Organization for Economic
Cooperation and Development (the "OECD"), or a political subdivision of any such
country, and having total assets in excess of $1,000,000,000, PROVIDED that such
bank is acting through a branch or agency located in the country in which it is
organized or another country which is also a member of the OECD; (iv) the
central bank of any country which is a member of the OECD; and (v) if, but only
if, any Event of Default has occurred and is continuing, any other bank,
insurance company, 

<PAGE>   14


                                      -7-


commercial finance company or other financial institution or other Person
approved by the Agent, such approval not to be unreasonably withheld.

     EMPLOYEE BENEFIT PLAN. Any employee benefit plan within the meaning of
[Section]3(3) of ERISA maintained or contributed to by the Borrower or Zycon,
other than a Guaranteed Pension Plan or a Multiemployer Plan.

     ENVIRONMENTAL LAWS. See [Section]7.18(a).

     ERISA. The Employee Retirement Income Security Act of 1974, as amended and
in effect from time to time.

     ERISA AFFILIATE. Any Person which is treated as a single employer with the
Borrower or Zycon under [Section]414 of the Code.

     ERISA REPORTABLE EVENT. A reportable event with respect to a Guaranteed
Pension Plan within the meaning of [Section]4043 of ERISA and the regulations
promulgated thereunder.

     EUROCURRENCY RESERVE RATE. For any day with respect to a Eurodollar Rate
Loan, the maximum rate (expressed as a decimal) at which any lender subject
thereto would be required to maintain reserves under Regulation D of the Board
of Governors of the Federal Reserve System (or any successor or similar
regulations relating to such reserve requirements) against "Eurocurrency
Liabilities" (as that term is used in Regulation D), if such liabilities were
outstanding. The Eurocurrency Reserve Rate shall be adjusted automatically on
and as of the effective date of any change in the Eurocurrency Reserve Rate.

     EURODOLLAR BUSINESS DAY. Any day on which commercial banks are open for
international business (including dealings in Dollar deposits) in London or such
other eurodollar interbank market as may be selected by the Agent in its sole
discretion acting in good faith.

     EURODOLLAR LENDING OFFICE. Initially, the office of each Bank designated as
such in SCHEDULE 1 hereto; thereafter, such other office of such Bank, if any,
that shall be making or maintaining Eurodollar Rate Loans.

     EURODOLLAR RATE. For any Interest Period with respect to a Eurodollar Rate
Loan, the rate of interest equal to (i) the arithmetic average of the rates per
annum (rounded upwards to the nearest 1/16 of one percent) of the rate at which
FNBB's Eurodollar Lending Office is offered Dollar deposits two Eurodollar
Business Days prior to the beginning of such Interest Period in the interbank
eurodollar market where the eurodollar and foreign currency and exchange
operations of such Eurodollar Lending Office are customarily conducted, for
delivery on the first day of such Interest Period for the number of days
comprised therein and in an amount comparable to the amount of the Eurodollar
Rate Loan of FNBB to which such Interest Period applies, divided by (ii) a
number equal to 1.00 minus the Eurocurrency Reserve Rate, if applicable.

<PAGE>   15


                                      -8-


     EURODOLLAR RATE LOANS. Loans bearing interest calculated by reference to
the Eurodollar Rate.

     EVENT OF DEFAULT. See [Section]13.1.

     FNBB. The First National Bank of Boston, a national banking association, in
its individual capacity.

     GENERALLY ACCEPTED ACCOUNTING PRINCIPLES. (i) When used in [Section]10,
whether directly or indirectly through reference to a capitalized term used
therein, means (A) principles that are consistent with the principles
promulgated or adopted by the Financial Accounting Standards Board and its
predecessors, in effect for the fiscal year ended on the Balance Sheet Date, and
(B) to the extent consistent with such principles, the accounting practice of
the Borrower reflected in its financial statements for the year ended on the
Balance Sheet Date, and (ii) when used in general, other than as provided above,
means principles that are (A) consistent with the principles promulgated or
adopted by the Financial Accounting Standards Board and its predecessors, as in
effect from time to time, and (B) consistently applied with past financial
statements of the Borrower adopting the same principles, provided that in each
case referred to in this definition of "generally accepted accounting
principles" a certified public accountant would, insofar as the use of such
accounting principles is pertinent, be in a position to deliver an unqualified
opinion (other than a qualification regarding changes in generally accepted
accounting principles) as to financial statements in which such principles have
been properly applied.

     GUARANTEED PENSION PLAN. Any employee pension benefit plan within the
meaning of [Section]3(2) of ERISA maintained or contributed to by the Borrower,
Zycon or any ERISA Affiliate the benefits of which are guaranteed on termination
in full or in part by the PBGC pursuant to Title IV of ERISA, other than a
Multiemployer Plan.

     GUARANTIES. The separate Guaranties, each in the form of EXHIBIT E-1 or, in
the case of the Guaranty to be entered into by Hadco Acquisition, of EXHIBIT E-2
hereto and dated or to be dated on, prior to or, in the case of Zycon Alternate
Circuits, Inc. and any Subsidiary which becomes a Guarantor pursuant to
[Section]9.5.2, after the Closing Date, made by each Guarantor in favor of the
Banks and the Agent pursuant to which such Guarantor guaranties to the Banks and
the Agent, to the extent provided therein, the payment and performance of the
Obligations.

     GUARANTORS. (i) Hadco Acquisition; (ii) immediately following the
consummation of the Merger, Zycon Alternate Circuits, Inc.; and (iii) any other
direct or indirect Subsidiary of the Borrower (other than Hadco FSC).

     GUARANTY DELIVERY DATE. The earliest to occur of (a) the consummation of
the Merger and the Borrower's and the other Transaction Parties' compliance with
the requirements of [Section]8.14 and (b) the date upon which the Securities no
longer constitute Margin Stock.

<PAGE>   16


                                      -9-


     HADCO ACQUISITION. Hadco Acquisition Corp., a Delaware corporation, and a
wholly owned subsidiary of the Borrower and from and after the Merger, shall
refer to the surviving entity of the Merger.

     HADCO FSC. Hadco Foreign Sales Corporation, a U.S. Virgin Islands
corporation.

     HAZARDOUS SUBSTANCES. See [Section]7.18(b).

     INDEBTEDNESS. All obligations, contingent and otherwise, that in accordance
with generally accepted accounting principles should be classified upon the
obligor's balance sheet as liabilities, or to which reference should be made by
footnotes thereto, including in any event and whether or not so classified: (i)
all debt and similar monetary obligations, whether direct or indirect; (ii) all
liabilities secured by any mortgage, pledge, security interest, lien, charge or
other encumbrance existing on property owned or acquired subject thereto,
whether or not the liability secured thereby shall have been assumed; and (iii)
all guarantees, endorsements and other contingent obligations whether direct or
indirect in respect of indebtedness of others, including any obligation to
supply funds to or in any manner to invest in, directly or indirectly, the
debtor, to purchase indebtedness, or to assure the owner of indebtedness against
loss, through an agreement to purchase goods, supplies, or services for the
purpose of enabling the debtor to make payment of the indebtedness held by such
owner or otherwise, and the obligations to reimburse the issuer in respect of
any letters of credit.

     INTEREST PAYMENT DATE. (i) As to any Base Rate Loan, the last day of the
calendar quarter which includes the Drawdown Date thereof; and (ii) as to any
Eurodollar Rate Loan in respect of which the Interest Period is (A) 3 months or
less, the last day of such Interest Period and (B) more than 3 months, the date
that is 3 months from the first day of such Interest Period and, in addition,
the last day of such Interest Period.

     INTEREST PERIOD. With respect to each Loan, (i) initially, the period
commencing on the Drawdown Date of such Loan and ending on the last day of one
of the periods set forth below, as selected by the Borrower in a Loan Request
(A) for any Base Rate Loan, the last day of the calendar quarter; and (B) for
any Eurodollar Rate Loan, 1, 2, 3 or 6 months; PROVIDED, HOWEVER, that during
the Syndication Period, the period for each Eurodollar Rate Loan shall be 1
month; and (ii) thereafter, each period commencing on the last day of the next
preceding Interest Period applicable to such Loan and ending on the last day of
one of the periods set forth above, as selected by the Borrower in a Conversion
Request; PROVIDED that all of the foregoing provisions relating to Interest
Periods are subject to the following:

          (a) if any Interest Period with respect to a Eurodollar Rate Loan
     would otherwise end on a day that is not a Eurodollar Business Day, that
     Interest Period shall be extended to the next succeeding Eurodollar
     Business Day unless the result of such extension would be to carry such

<PAGE>   17

                                      -10-


     Interest Period into another calendar month, in which event such Interest
     Period shall end on the immediately preceding Eurodollar Business Day;

          (b) if any Interest Period with respect to a Base Rate Loan would end
     on a day that is not a Business Day, that Interest Period shall end on the
     next succeeding Business Day;

          (c) if the Borrower shall fail to give notice as provided in
     [Section]2.7, the Borrower shall be deemed to have requested a conversion
     of the affected Eurodollar Rate Loan to a Base Rate Loan and the
     continuance of all Base Rate Loans as Base Rate Loans on the last day of
     the then current Interest Period with respect thereto;

          (d) any Interest Period relating to any Eurodollar Rate Loan that
     begins on the last Eurodollar Business Day of a calendar month (or on a day
     for which there is no numerically corresponding day in the calendar month
     at the end of such Interest Period) shall end on the last Eurodollar
     Business Day of a calendar month; and

          (e) any Interest Period relating to any Eurodollar Rate Loan that
     would otherwise extend beyond the Revolving Credit Loan Maturity Date shall
     end on the Revolving Credit Loan Maturity Date.

     INVESTMENTS. All expenditures made and all liabilities incurred
(contingently or otherwise) for the acquisition of stock or Indebtedness of, or
for loans, advances, capital contributions or transfers of property to, or in
respect of any guaranties (or other commitments as described under
Indebtedness), or obligations of, any Person. In determining the aggregate
amount of Investments outstanding at any particular time: (i) the amount of any
Investment represented by a guaranty shall be taken at not less than the
principal amount of the obligations guaranteed and still outstanding; (ii) there
shall be included as an Investment all interest accrued with respect to
Indebtedness constituting an Investment unless and until such interest is paid;
(iii) there shall be deducted in respect of each such Investment any amount
received as a return of capital (but only by repurchase, redemption, retirement,
repayment, liquidating dividend or liquidating distribution); (iv) there shall
not be deducted in respect of any Investment any amounts received as earnings on
such Investment, whether as dividends, interest or otherwise, except that
accrued interest included as provided in the foregoing clause (ii) may be
deducted when paid; and (v) there shall not be deducted from the aggregate
amount of Investments any decrease in the value thereof.

     LETTER OF CREDIT. See [Section]4.1.1.

     LETTER OF CREDIT APPLICATION. See [Section]4.1.1.

     LETTER OF CREDIT PARTICIPATION. See [Section]4.1.4.


<PAGE>   18


                                      -11-


     LOAN DOCUMENTS. This Credit Agreement, the Notes, the Letter of Credit
Applications, the Letters of Credit, the Guaranties, the Stock Pledge Agreement,
the Agent's Side Letter, any interest rate protection agreements entered into
with any of the Banks in connection herewith and any other instruments,
documents and agreements executed from time to time in connection herewith.

     LOAN REQUEST. See [Section]2.6.

     LOANS. Revolving credit loans made or to be made by the Banks to the
Borrower pursuant to [Section]2.

     MAJORITY BANKS. As of any date, the Banks holding at least fifty-one
percent (51%) of the outstanding principal amount of the Notes on such date; and
if no such principal is outstanding, the Banks whose aggregate Commitments
constitutes at least fifty-one percent (51%) of the Total Commitment.

     MARGIN STOCK. "Margin stock" or "margin securities", as such terms are used
in Regulations U and X of the Board of Governors of the Federal Reserve System,
12 C.F.R. Parts 221 and 224.

     MAXIMUM DRAWING AMOUNT. The maximum aggregate amount that the beneficiaries
may at any time draw under outstanding Letters of Credit, as such aggregate
amount may be reduced from time to time pursuant to the terms of the Letters of
Credit.

     MAXIMUM GUARANTEED LOAN VALUE. "Maximum loan value" as used and defined in
Section 221.8 of Regulation U of the Board of Governors of the Federal Reserve
System, 12 C.F.R. [Section]221.8.

     MERGER. As contemplated by the Merger Documents, the merger of Hadco
Acquisition with and into Zycon, with Hadco Acquisition as the surviving entity.

     MERGER DOCUMENTS. The Agreement and Plan of Merger, dated December 4, 1996
among the Borrower, Hadco Acquisition and Zycon, together with all schedules,
exhibits and annexes thereto, and all agreements and documents entered into or
required to be entered into and delivered pursuant to such Agreement and Plan of
Merger or in connection with the Merger, including the Stockholders Agreement
dated December 4, 1996 among the Borrower, Hadco Acquisition and certain selling
shareholders of Zycon.

     MULTIEMPLOYER PLAN. Any multiemployer plan within the meaning of
[Section]3(37) of ERISA maintained or contributed to by the Borrower or any
ERISA Affiliate.

     NOTES. See [Section]2.4.

     OBLIGATIONS. All indebtedness, obligations and liabilities of any of the
Transaction Parties to any of the Banks and the Agent, individually or
collectively, existing on the date of this Credit Agreement or arising
thereafter, 

<PAGE>   19


                                      -12-

direct or indirect, joint or several, absolute or contingent, matured or
unmatured, liquidated or unliquidated, secured or unsecured, arising by
contract, operation of law or otherwise, arising or incurred under this Credit
Agreement or any of the other Loan Documents or in respect of any of the Loans
made or Reimbursement Obligations incurred or any of the Notes, Letter of Credit
Application, Letter of Credit or other instruments at any time evidencing any
thereof.

     OUTSTANDING. With respect to the Loans, the aggregate unpaid principal
thereof as of any date of determination.

     PBGC. The Pension Benefit Guaranty Corporation created by [Section]4002 of
ERISA and any successor entity or entities having similar responsibilities.

     PERMITTED ACQUISITIONS. Acquisitions of stock or assets permitted by
[Section]9.5.1.

     PERMITTED LIENS. Liens, security interests and other encumbrances permitted
by [Section]9.2.

     PERSON. Any individual, corporation, partnership, trust, unincorporated
association, business, or other legal entity, and any government or any
governmental agency or political subdivision thereof.

     PRO FORMA BALANCE SHEET. See [Section]7.4.3.

     REAL ESTATE. All real property at any time owned or leased (as lessee or
sublessee) by any of the Transaction Parties.

     REIMBURSEMENT OBLIGATION. The Borrower's obligation to reimburse the Agent
and the Banks on account of any drawing under any Letter of Credit as provided
in [Section]4.2.

     REVOLVING CREDIT LOAN MATURITY DATE. January 8, 2002.

     SECURITIES. Shares of the outstanding common stock, $.001 par value per
share of Zycon, to be purchased pursuant to the Tender Offer.

     STOCK PLEDGE AGREEMENT. The Stock Pledge Agreement in the form of EXHIBIT F
hereto, dated or to be dated on or prior to the Closing Date, made by Hadco
Acquisition in favor of the Agent and the Banks, pursuant to which Hadco
Acquisition will, until the consummation of the Merger and the compliance by the
Borrower and the other Transaction Parties with the requirements of
[Section]8.14, pledge the Securities in order to secure its obligations under
its Guaranty.

     SUBSIDIARY. Any corporation, association, trust, or other business entity
of which the designated parent shall at any time own directly or indirectly
through a Subsidiary or Subsidiaries at least a majority (by number of votes) of
the outstanding Voting Stock.

<PAGE>   20

                                      -13-


     SYNDICATION PERIOD. The period from the Closing Date until such time as the
Agent shall have concluded the syndication of this Credit Agreement and the
other Loan Documents on terms and conditions satisfactory to the Agent in its
sole discretion.

     TARGET. See [Section]9.5.2.

     TENDER OFFER. The offer to purchase the Securities pursuant to the Tender
Offer Documents.

     TENDER OFFER DOCUMENTS. The Offer to Purchase dated December 11, 1996 from
Hadco Acquisition to the holders of the Securities, as amended or supplemented
from time to time thereafter in accordance with [Section]9.9 hereof, and all
amendments and instruments required to be entered into or delivered by the
Borrower pursuant to such Offer to Purchase in order to complete the purchase of
the Securities contemplated by the Tender Offer, as amended or supplemented from
time to time in accordance with [Section]9.9 hereof.

     TOTAL COMMITMENT. The sum of the Commitments of the Banks, as in effect
from time to time.

     TRANSACTION DOCUMENTS. Collectively, the Loan Documents, the Tender Offer
Documents and the Merger Documents.

     TRANSACTION PARTIES. Collectively, the Borrower and its Subsidiaries and
Zycon and its Subsidiaries.

     TYPE. As to any Loan, its nature as a Base Rate Loan or a Eurodollar Rate
Loan.

     UNIFORM CUSTOMS. With respect to any Letter of Credit, the Uniform Customs
and Practice for Documentary Credits (1993 Revision), International Chamber of
Commerce Publication No. 500 or any successor version thereto adopted by the
Agent in the ordinary course of its business as a letter of credit issuer and in
effect at the time of issuance of such Letter of Credit.

     UNPAID REIMBURSEMENT OBLIGATION. Any Reimbursement Obligation for which the
Borrower does not reimburse the Agent and the Banks on the date specified in,
and in accordance with, [Section]4.2.

     VOTING STOCK. Stock or similar interests, of any class or classes (however
designated), the holders of which are at the time entitled, as such holders, to
vote for the election of a majority of the directors (or persons performing
similar functions) of the corporation, association, trust or other business
entity involved, whether or not the right so to vote exists by reason of the
happening of a contingency.

     ZYCON. Zycon Corporation, a Delaware corporation, and the issuer of the
Securities, but not the surviving entity of the Merger.

<PAGE>   21


                                      -14-


     ZYCON BALANCE SHEET DATE. November 30, 1996.

     ZYCON EMPLOYEE DISTRIBUTION. The Distribution made by Hadco Acquisition
upon the consummation of the Merger, in an aggregate amount not to exceed
$6,000,000, in order to pay employees of Zycon the difference between the
exercise price of the stock options owned by such employees and the price per
share offered by Hadco Acquisition for the Securities in connection with the
Tender Offer.

     1.2. RULES OF INTERPRETATION.
          -----------------------

          (a) A reference to any document or agreement shall include such
     document or agreement as amended, modified or supplemented from time to
     time in accordance with its terms and the terms of this Credit Agreement.

          (b) The singular includes the plural and the plural includes the
     singular.

          (c) A reference to any law includes any amendment or modification to
     such law.

          (d) A reference to any Person includes its permitted successors and
     permitted assigns.

          (e) Accounting terms not otherwise defined herein have the meanings
     assigned to them by generally accepted accounting principles applied on a
     consistent basis by the accounting entity to which they refer.

          (f) The words "include", "includes" and "including" are not limiting.

          (g) All terms not specifically defined herein or by generally accepted
     accounting principles, which terms are defined in the Uniform Commercial
     Code as in effect in the Commonwealth of Massachusetts, have the meanings
     assigned to them therein, with the term "instrument" being that defined
     under Article 9 of the Uniform Commercial Code.

          (h) Reference to a particular "[Section]" refers to that section of
     this Credit Agreement unless otherwise indicated.

          (i) The words "herein", "hereof", "hereunder" and words of like import
     shall refer to this Credit Agreement as a whole and not to any particular
     section or subdivision of this Credit Agreement.

                        2. THE REVOLVING CREDIT FACILITY.
                           -----------------------------

     2.1. COMMITMENT TO LEND. Subject to the terms and conditions set forth in
this Credit Agreement, each of the Banks severally agrees to lend to the
Borrower and the Borrower may borrow, repay, and reborrow from time to time

<PAGE>   22


                                      -15-


between the Closing Date and the Revolving Credit Loan Maturity Date upon notice
by the Borrower to the Agent given in accordance with [Section]2.6, such sums as
are requested by the Borrower up to a maximum aggregate amount outstanding
(after giving effect to all amounts requested) at any one time equal to such
Bank's Commitment MINUS such Bank's Commitment Percentage of the sum of the
Maximum Drawing Amount and all Unpaid Reimbursement Obligations, PROVIDED that
the sum of the outstanding amount of the Loans (after giving effect to all
amounts requested) PLUS the Maximum Drawing Amount and all Unpaid Reimbursement
Obligations shall not at any time exceed the Total Commitment. The Loans shall
be made PRO RATA in accordance with each Bank's Commitment Percentage. Each
request for a Loan hereunder shall constitute a representation and warranty by
the Borrower that the conditions set forth in [Section]11 and [Section]12, in
the case of the initial Loans to be made on the Closing Date, and [Section]12,
in the case of all other Loans, have been satisfied on the date of such request.


     2.2. COMMITMENT FEE. The Borrower agrees to pay to the Agent for the
accounts of the Banks in accordance with their respective Commitment Percentages
a commitment fee calculated at a rate per annum equal to the Applicable
Commitment Fee Percentage on the average daily amount during each calendar
quarter or portion thereof from Closing Date to the Revolving Credit Loan
Maturity Date by which the Total Commitment MINUS the sum of the Maximum Drawing
Amount and all Unpaid Reimbursement Obligations exceeds the outstanding amount
of Loans during such calendar quarter. The commitment fee shall be payable
quarterly in arrears on the first day of each calendar quarter for the
immediately preceding calendar quarter commencing on the first such date
following the date hereof, with a final payment on the Revolving Credit Loan
Maturity Date or any earlier date on which the Commitments shall terminate.


     2.3. REDUCTION OF TOTAL COMMITMENT. Upon the Borrower's incurrence of any
Indebtedness permitted by [Section] 9.1(k), the Borrower shall, at the request
of the Majority Banks, reduce the Total Commitment by an amount equal to the net
proceeds of all such Indebtedness incurred following the Closing Date, up to a
maximum of $50,000,000 in connection with any such Indebtedness described in
[Section]9.1(k)(i) and up to a maximum of $100,000,000 in connection with any
such Indebtedness described in [Section]9.1(k)(ii). The Borrower shall have the
right, without penalty (other than breakage fees relating to Eurodollar Rate
Loans for which the Borrower is otherwise responsible under [Section]5.9 and as
otherwise provided in this [Section]2.3), at any time and from time to time upon
seven (7) Business Days prior written notice to the Agent to reduce by
$10,000,000 or an integral multiple of $5,000,000 in excess thereof or terminate
entirely the Total Commitment; PROVIDED, HOWEVER, that the Total Commitment
shall not be reduced below $50,000,000 unless it is terminated in full; and
PROVIDED FURTHER that if, within one (1) year following the Closing Date, the
Borrower incurs Indebtedness permitted by [Section]9.1(k) or sells equity
securities of the Borrower, or warrants or subscription rights for equity
securities of the Borrower, the sale or issuance of any of which does not create
or result in a Default or Event of Default, in an aggregate amount for all such
Indebtedness 

<PAGE>   23


                                      -16-


and net proceeds of the sale of such equity securities, or warrants
or subscription rights for equity securities, in excess of $75,000,000, and the
Borrower, at its option, reduces the Total Commitment by more than $75,000,000,
the Borrower shall, at the time of such reduction of the Total Commitment, pay
to the Agent, for the PRO RATA benefit of the Banks, a fee equal to one fifth of
one percent (.20%) on the amount by which such reduction in the Total Commitment
exceeds $75,000,000. Upon any such reduction of the Total Commitment as set
forth in either of the two immediately preceding sentences, the Commitments of
the Banks shall be reduced PRO RATA in accordance with their respective
Commitment Percentages of the amount specified in such notice or, as the case
may be, terminated. Promptly after receiving any notice of the Borrower
delivered pursuant to this [Section]2.3.2, the Agent will notify the Banks of
the substance thereof. Upon the effective date of any such reduction or
termination, the Borrower shall pay to the Agent for the respective accounts of
the Banks the full amount of any commitment fee then accrued on the amount of
the reduction. No reduction or termination of the Commitments may be reinstated.


     2.4. THE NOTES. The Loans shall be evidenced by separate promissory notes
of the Borrower in substantially the form of EXHIBIT A hereto (each a "Note"),
dated as of the Closing Date and completed with appropriate insertions. One Note
shall be payable to the order of each Bank in a principal amount equal to such
Bank's Commitment or, if less, the outstanding amount of all Loans made by such
Bank, plus interest accrued thereon, as set forth below. The Borrower
irrevocably authorizes each Bank to make or cause to be made, at or about the
time of the Drawdown Date of any Loan or at the time of receipt of any payment
of principal on such Bank's Note, an appropriate computer entry or other record
reflecting the making of such Loan or (as the case may be) the receipt of such
payment. The outstanding amount of the Loans set forth in such computer entries
or other records shall be PRIMA FACIE evidence of the principal amount thereof
owing and unpaid to such Bank, but the failure to record, or any error in so
recording, any such amount in such computer entries or other records shall not
limit or otherwise affect the obligations of the Borrower hereunder or under any
Note to make payments of principal of or interest on any Note when due.


     2.5. INTEREST ON LOANS. Except as otherwise provided in [Section]5.10,

          (a) Each Base Rate Loan shall bear interest for the period commencing
     with the Drawdown Date thereof and ending on the last day of the Interest
     Period with respect thereto at a rate per annum equal to the Base Rate.

          (b) Each Eurodollar Rate Loan shall bear interest for the period
     commencing with the Drawdown Date thereof and ending on the last day of the
     Interest Period with respect thereto at a rate per annum equal to the
     Applicable Eurodollar Rate Margin PLUS the Eurodollar Rate determined for
     such Interest Period.


<PAGE>   24


                                      -17-


          (c) The Borrower promises to pay interest on each Loan in arrears on
     each Interest Payment Date with respect thereto.


     2.6. REQUESTS FOR LOANS. The Borrower shall give to the Agent written
notice in the form of EXHIBIT B hereto (or telephonic notice confirmed in a
writing in the form of EXHIBIT B hereto) of each Loan requested hereunder (a
"Loan Request") no less than (i) one (1) Business Day prior to the proposed
Drawdown Date of any Base Rate Loan and (ii) three (3) Eurodollar Business Days
prior to the proposed Drawdown Date of any Eurodollar Rate Loan. Each such
notice shall specify (A) the principal amount of the Loan requested, (B) the
proposed Drawdown Date of such Loan, (C) the Interest Period for such Revolving
Credit Loan and (D) the Type of such Loan. Promptly upon receipt of any such
notice, the Agent shall notify each of the Banks thereof. Each Loan Request
shall be irrevocable and binding on the Borrower and shall obligate the Borrower
to accept the Loan requested from the Banks on the proposed Drawdown Date. Each
Loan Request shall be in a minimum aggregate amount of $5,000,000 or an integral
multiple thereof.

     2.7. CONVERSION OPTIONS.
          ------------------

          2.7.1. CONVERSION TO DIFFERENT TYPE OF LOAN. The Borrower may elect
     from time to time to convert any outstanding Loan to a Loan of another
     Type, PROVIDED that (i) with respect to any such conversion of a Loan to a
     Base Rate Loan, the Borrower shall give the Agent at least one (1) Business
     Day prior written notice of such election; (ii) with respect to any such
     conversion of a Base Rate Loan to a Eurodollar Rate Loan, the Borrower
     shall give the Agent at least three (3) Eurodollar Business Days prior
     written notice of such election; (iii) with respect to any such conversion
     of a Eurodollar Rate Loan into a Loan of another Type, such conversion
     shall only be made on the last day of the Interest Period with respect
     thereto; and (iv) no Loan may be converted into a Eurodollar Rate Loan when
     any Default or Event of Default has occurred and is continuing. On the date
     on which such conversion is being made, each Bank shall take such action as
     is necessary to transfer its Commitment Percentage of such Loans to its
     Domestic Lending Office or its Eurodollar Lending Office, as the case may
     be. All or any part of outstanding Loans of any Type may be converted into
     a Loan of another Type as provided herein, PROVIDED that any partial
     conversion shall be in an aggregate principal amount of $5,000,000 or a
     whole multiple thereof. Each Conversion Request relating to the conversion
     of a Loan to a Eurodollar Rate Loan shall be irrevocable by the Borrower.


          2.7.2. CONTINUATION OF TYPE OF LOAN. Any Loan of any Type may be
     continued as a Loan of the same Type upon the expiration of an Interest
     Period with respect thereto by compliance by the Borrower with the notice
     provisions contained in [Section]2.7.1; PROVIDED that no Eurodollar Rate
     Loan may be continued as such when any Default or Event of Default has
     occurred and is continuing, but shall be automatically converted to a Base
     Rate Loan on the last day of the first Interest Period 

<PAGE>   25


                                      -18-


     relating thereto ending during the continuance of any Default or Event of
     Default of which officers of the Agent active upon the Borrower's account
     have actual knowledge. In the event that the Borrower fails to provide any
     such notice with respect to the continuation of any Eurodollar Rate Loan as
     such, then such Eurodollar Rate Loan shall be automatically converted to a
     Base Rate Loan on the last day of the first Interest Period relating
     thereto. The Agent shall notify the Banks promptly when any such automatic
     conversion contemplated by this [Section]2.7 is scheduled to occur.


          2.7.3. EURODOLLAR RATE LOANS. Any conversion to or from Eurodollar
     Rate Loans shall be in such amounts and be made pursuant to such elections
     so that, after giving effect thereto, the aggregate principal amount of all
     Eurodollar Rate Loans having the same Interest Period shall not be less
     than $20,000,000 or a whole multiple of $5,000,000 in excess thereof. At no
     time shall there be more than five (5) Eurodollar Rate Loans outstanding.

     2.8. FUNDS FOR LOANS.
          ---------------

          2.8.1. FUNDING PROCEDURES. Not later than 11:00 a.m. (Boston time) on
     the proposed Drawdown Date of any Loans, each of the Banks will make
     available to the Agent, at its Head Office, in immediately available funds,
     the amount of such Bank's Commitment Percentage of the amount of the
     requested Loans. Upon receipt from each Bank of such amount, and upon
     receipt of the documents required by [Section][Section]11 and 12 and the
     satisfaction of the other conditions set forth therein, to the extent
     applicable, the Agent will make available to the Borrower the aggregate
     amount of such Loans made available to the Agent by the Banks. The failure
     or refusal of any Bank to make available to the Agent at the aforesaid time
     and place on any Drawdown Date the amount of its Commitment Percentage of
     the requested Loans shall not relieve any other Bank from its several
     obligation hereunder to make available to the Agent the amount of such
     other Bank's Commitment Percentage of any requested Loans.


          2.8.2. ADVANCES BY AGENT. The Agent may, unless notified to the
     contrary by any Bank prior to a Drawdown Date, assume that such Bank has
     made available to the Agent on such Drawdown Date the amount of such Bank's
     Commitment Percentage of the Loans to be made on such Drawdown Date, and
     the Agent may (but it shall not be required to), in reliance upon such
     assumption, make available to the Borrower a corresponding amount. If any
     Bank makes available to the Agent such amount on a date after such Drawdown
     Date, such Bank shall pay to the Agent on demand an amount equal to the
     product of (i) the average computed for the period referred to in clause
     (iii) below, of the weighted average interest rate paid by the Agent for
     federal funds acquired by the Agent during each day included in such
     period, TIMES (ii) the amount of such Bank's Commitment Percentage of such
     Loans, TIMES (iii) a fraction, the numerator of which is the number of days
     that elapse from and 

<PAGE>   26


                                      -19-


     including such Drawdown Date to the date on which the amount of such Bank's
     Commitment Percentage of such Loans shall become immediately available to
     the Agent, and the denominator of which is 360. A statement of the Agent
     submitted to such Bank with respect to any amounts owing under this
     paragraph shall be PRIMA FACIE evidence of the amount due and owing to the
     Agent by such Bank. If the amount of such Bank's Commitment Percentage of
     such Loans is not made available to the Agent by such Bank within three (3)
     Business Days following such Drawdown Date, the Agent shall be entitled to
     recover such amount from the Borrower on demand, with interest thereon at
     the rate per annum applicable to the Loans made on such Drawdown Date.

                   3. REPAYMENT OF THE REVOLVING CREDIT LOANS.
                      ---------------------------------------

     3.1. MATURITY. The Borrower promises to pay on the Revolving Credit Loan
Maturity Date, and there shall become absolutely due and payable on the
Revolving Credit Loan Maturity Date, all of the Loans outstanding on such date,
together with any and all accrued and unpaid interest thereon.

     3.2. MANDATORY REPAYMENTS OF LOANS. If at any time the Borrower shall incur
Indebtedness permitted by [Section]9.1(k), the Borrower shall, at the request of
the Majority Banks, immediately pay to the Agent for the respective accounts of
the Banks an amount equal to the net proceeds of all such Indebtedness incurred
following the Closing Date, up to a maximum of $50,000,000 in connection with
any such Indebtedness described in [Section]9.1(k)(i) and up to a maximum of
$100,000,000 in connection with any such Indebtedness described in
[Section]9.1(k)(ii). If at any time the sum of the outstanding amount of the
Loans, the Maximum Drawing Amount and all Unpaid Reimbursement Obligations
exceeds the Total Commitment, then the Borrower shall immediately pay the amount
of such excess to the Agent for the respective accounts of the Banks. Any
amounts repaid in accordance with either of the immediately preceding two
sentences shall be applied: first, to any Unpaid Reimbursement Obligations;
second, to the Loans; and third, to provide to the Agent cash collateral for
Reimbursement Obligations as contemplated by [Section]4.2(b) and (c). Each
payment of any Unpaid Reimbursement Obligations or prepayment of Loans shall be
allocated among the Banks, in proportion, as nearly as practicable, to each
Reimbursement Obligation or (as the case may be) the respective unpaid principal
amount of each Bank's Note, with adjustments to the extent practicable to
equalize any prior payments or repayments not exactly in proportion.


     3.3. OPTIONAL REPAYMENTS OF LOANS. The Borrower shall have the right, at
its election, to repay the outstanding amount of the Loans, as a whole or in
part, at any time without penalty or premium, PROVIDED that any full or partial
prepayment of the outstanding amount of any Eurodollar Rate Loans pursuant to
this [Section]3.3 may be made only on the last day of the Interest Period
relating thereto. The Borrower shall give the Agent, no later than 10:00 a.m.,
Boston time, at least one (1) Business Day prior written notice of any proposed
prepayment pursuant to this [Section]3.3 of Base Rate Loans, and three (3)
Eurodollar 

<PAGE>   27


                                      -20-


Business Days notice of any proposed prepayment pursuant to this [Section]3.3 of
Eurodollar Rate Loans, in each case specifying the proposed date of prepayment
of Loans and the principal amount to be prepaid. Each such partial prepayment of
the Loans shall be in an integral multiple of $5,000,000 and shall be applied,
in the absence of instruction by the Borrower, first to the principal of Base
Rate Loans and then to the principal of Eurodollar Rate Loans. Accrued interest
on the principal prepaid in connection with each such partial prepayment shall
be due and payable on the next Interest Payment Date, but accrued interest on
the principal paid in connection with any full prepayment at a time when the
Total Commitment is terminated shall be paid on the date of prepayment. Each
prepayment shall be allocated among the Banks, in proportion, as nearly as
practicable, to the respective unpaid principal amount of each Bank's Note, with
adjustments to the extent practicable to equalize any prior repayments not
exactly in proportion.

                              4. LETTERS OF CREDIT.
                                 -----------------


     4.1. LETTER OF CREDIT COMMITMENTS.
          ----------------------------

          4.1.1. COMMITMENT TO ISSUE LETTER OF CREDIT. Subject to the terms and
     conditions hereof and the execution and delivery by the Borrower of a
     letter of credit application on the Agent's customary form (a "Letter of
     Credit Application"), the Agent on behalf of the Banks and in reliance upon
     the agreement of the Banks set forth in [Section]4.1.4 and upon the
     representations and warranties of the Borrower contained herein, agrees, in
     its individual capacity, to issue, extend and renew for the account of the
     Borrower one or more standby or documentary letters of credit
     (individually, a "Letter of Credit"), in such form as may be requested from
     time to time by the Borrower and agreed to by the Agent; PROVIDED, HOWEVER,
     that, after giving effect to such request, (a) the sum of the aggregate
     Maximum Drawing Amount and all Unpaid Reimbursement Obligations shall not
     exceed $15,000,000 at any one time and (b) the sum of (i) the Maximum
     Drawing Amount on all Letters of Credit, (ii) all Unpaid Reimbursement
     Obligations, and (iii) the amount of all Loans outstanding (after giving
     effect to all amounts requested) shall not exceed the Total Commitment.


          4.1.2. LETTER OF CREDIT APPLICATIONS. Each Letter of Credit
     Application shall be completed to the satisfaction of the Agent. In the
     event that any provision of any Letter of Credit Application shall be
     inconsistent with any provision of this Credit Agreement, then the
     provisions of this Credit Agreement shall, to the extent of any such
     inconsistency, govern.


          4.1.3. TERMS OF LETTERS OF CREDIT. Each Letter of Credit issued,
     extended or renewed hereunder shall, among other things, (i) provide for
     the payment of sight drafts for honor thereunder when presented in
     accordance with the terms thereof and when accompanied by the documents
     described therein, (ii) have an expiry date (which may be 

<PAGE>   28


                                      -21-


     extended annually by the Agent, at its option upon the request of the
     Borrower) no more than one year following its date of issue and (iii) have
     an expiry date no later than the date which is fourteen (14) days (or, if
     the Letter of Credit is confirmed by a confirmer or otherwise provides for
     one or more nominated persons, forty-five (45) days) prior to the Revolving
     Credit Loan Maturity Date. Each Letter of Credit so issued, extended or
     renewed shall be subject to the Uniform Customs.


          4.1.4. REIMBURSEMENT OBLIGATIONS OF BANKS. Each Bank severally agrees
     that it shall be absolutely liable, without regard to the occurrence of any
     Default or Event of Default or any other condition precedent whatsoever, to
     the extent of such Bank's Commitment Percentage, to reimburse the Agent on
     demand for the amount of each draft paid by the Agent under each Letter of
     Credit to the extent that such amount is not reimbursed by the Borrower
     pursuant to [Section]4.2 (such agreement for a Bank being called herein the
     "Letter of Credit Participation" of such Bank).


          4.1.5. PARTICIPATIONS OF BANKS. Each such payment made by a Bank shall
     be treated as the purchase by such Bank of a participating interest in the
     Borrower's Reimbursement Obligation under [Section]4.2 in an amount equal
     to such payment. Each Bank shall share in accordance with its participating
     interest in any interest which accrues pursuant to [Section]4.2.


     4.2. REIMBURSEMENT OBLIGATION OF THE BORROWER. In order to induce the Agent
to issue, extend and renew each Letter of Credit and the Banks to participate
therein, the Borrower hereby agrees to reimburse or pay to the Agent, for the
account of the Agent or (as the case may be) the Banks, with respect to each
Letter of Credit issued, extended or renewed by the Agent hereunder,

          (a) except as otherwise expressly provided in [Section]4.2(b) and (c),
     on each date that any draft presented under such Letter of Credit is
     honored by the Agent, or the Agent otherwise makes a payment with respect
     thereto, (i) the amount paid by the Agent under or with respect to such
     Letter of Credit, and (ii) the amount of any taxes, fees, charges or other
     reasonable costs and expenses whatsoever incurred by the Agent or any Bank
     in connection with any payment made by the Agent or any Bank under, or with
     respect to, such Letter of Credit,

          (b) upon the reduction (but not termination) of the Total Commitment
     to an amount less than the Maximum Drawing Amount, an amount equal to such
     difference, which amount shall be held by the Agent for the benefit of the
     Banks and the Agent in an interest bearing account selected by the Agent as
     cash collateral for all Reimbursement Obligations, and

<PAGE>   29


                                      -22-


          (c) upon the termination of the Total Commitment, or the acceleration
     of the Reimbursement Obligations with respect to all Letters of Credit in
     accordance with [Section]13, an amount equal to the then Maximum Drawing
     Amount on all Letters of Credit, which amount shall be held by the Agent
     for the benefit of the Banks and the Agent in an interest bearing account
     selected by the Agent as cash collateral for all Reimbursement Obligations.

Each such payment shall be made to the Agent at the Agent's Head Office in
immediately available funds. Interest on any and all amounts remaining unpaid by
the Borrower under this [Section]4.2 at any time from the date such amounts
become due and payable (whether as stated in this [Section]4.2, by acceleration
or otherwise) until payment in full (whether before or after judgment) shall be
payable to the Agent on demand at the rate specified in [Section]5.10 for
overdue principal on the Loans. So long as no Default or Event of Default has
occurred and is continuing, the Agent shall return amounts held as cash
collateral pursuant to [Section]4.2(b) or as a result of the Borrower's
termination of the Total Commitment pursuant to [Section]4.2(c) within a
reasonable time following the expiration or cancellation of any Letter of
Credit, with the amount being so returned equal to the Maximum Drawing Amount of
such expired or cancelled Letter of Credit.


     4.3. LETTER OF CREDIT PAYMENTS. If any draft shall be presented or other
demand for payment shall be made under any Letter of Credit, the Agent shall
notify the Borrower of the date and amount of the draft presented or demand for
payment and of the date and time when it expects to pay such draft or honor such
demand for payment. If the Borrower fails to reimburse the Agent as provided in
[Section]4.2 on or before the date that such draft is paid or other payment is
made by the Agent, the Agent may at any time thereafter notify the Banks of the
amount of any such Unpaid Reimbursement Obligation. No later than 3:00 p.m.
(Boston time) on the Business Day next following the receipt of such notice,
each Bank shall make available to the Agent, at its Head Office, in immediately
available funds, such Bank's Commitment Percentage of such Unpaid Reimbursement
Obligation, together with an amount equal to the product of (i) the average,
computed for the period referred to in clause (iii) below, of the weighted
average interest rate paid by the Agent for federal funds acquired by the Agent
during each day included in such period, TIMES (ii) the amount equal to such
Bank's Commitment Percentage of such Unpaid Reimbursement Obligation, TIMES
(iii) a fraction, the numerator of which is the number of days that elapse from
and including the date the Agent paid the draft presented for honor or otherwise
made payment to the date on which such Bank's Commitment Percentage of such
Unpaid Reimbursement obligation shall become immediately available to the Agent,
and the denominator of which is 360. The responsibility of the Agent to the
Borrower and the Banks shall be only to determine that the documents (including
each draft) delivered under each Letter of Credit in connection with such
presentment shall be in conformity in all material respects with such Letter of
Credit, and upon such determination, the Agent shall honor a demand for payment
under such Letter of Credit.

<PAGE>   30


                                      -23-



     4.4. OBLIGATIONS ABSOLUTE. The Borrower's obligations under this [Section]4
shall be absolute and unconditional under any and all circumstances and
irrespective, so long as the Agent has honored any appropriate demand for
payment with respect to any Letter of Credit, of the occurrence of any Default
or Event of Default or any condition precedent whatsoever or any setoff,
counterclaim or defense to payment which the Borrower may have or have had
against the Agent, any Bank or any beneficiary of a Letter of Credit. The
Borrower further agrees with the Agent and the Banks that the Agent and the
Banks shall not be responsible for, and the Borrower's Reimbursement Obligations
under [Section]4.2 shall not be affected by, among other things, the validity or
genuineness of documents or of any endorsements thereon, even if such documents
should in fact prove to be in any or all respects invalid, fraudulent or forged,
or any dispute between or among the Borrower, the beneficiary of any Letter of
Credit or any financing institution or other party to which any Letter of Credit
may be transferred or any claims or defenses whatsoever of the Borrower against
the beneficiary of any Letter of Credit or any such transferee. The Agent and
the Banks shall not be liable for any error, omission, interruption or delay in
transmission, dispatch or delivery of any message or advice, however
transmitted, in connection with any Letter of Credit. The Borrower agrees that
any action taken or omitted by the Agent or any Bank under or in connection with
each Letter of Credit and the related drafts and documents, if done in good
faith and with commercial reasonableness, shall be binding upon the Borrower and
shall not result in any liability on the part of the Agent or any Bank to the
Borrower.


     4.5. RELIANCE BY ISSUER. To the extent not inconsistent with [Section]4.4,
the Agent shall be entitled to rely, and shall be fully protected in relying
upon, any Letter of Credit, draft, writing, resolution, notice, consent,
certificate, affidavit, letter, cablegram, telegram, telecopy, telex or teletype
message, statement, order or other document believed by it to be genuine and
correct and to have been signed, sent or made by the proper Person or Persons
and upon advice and statements of legal counsel, independent accountants and
other experts selected by the Agent. The Agent shall be fully justified in
failing or refusing to take any action under this Agreement unless it shall
first have received such advice or concurrence of the Majority Banks as it
reasonably deems appropriate or it shall first be indemnified to its reasonable
satisfaction by the Banks against any and all liability and expense which may be
incurred by it by reason of taking or continuing to take any such action. The
Agent shall in all cases be fully protected in acting, or in refraining from
acting, under this Agreement in accordance with a request of the Majority Banks,
and such request and any action taken or failure to act pursuant thereto shall
be binding upon the Banks and all future holders of the Notes or of a Letter of
Credit Participation.


     4.6. LETTER OF CREDIT FEE. The Borrower shall, on the date of issuance or
any extension or renewal of any Letter of Credit and at such other time or times
as such charges are customarily made by the Agent, pay a fee (in each case, a
"Letter of Credit Fee") to the Agent (i) in respect of each standby Letter of
Credit equal to (A) the Applicable Eurodollar Rate Margin in effect on such date
MULTIPLIED BY the face amount of such standby Letter of Credit PLUS (B) the

<PAGE>   31


                                      -24-


Agent's customary issuance fee PLUS (C) a fronting fee (for the account of the
Agent) equal to one-eighth of one percent (0.125)% per annum of the face amount
of such standby Letter of Credit, and (ii) in respect of each documentary Letter
of Credit equal to (A) the Agent's customary administrative fees PLUS (B) the
Applicable Eurodollar Rate Margin in effect on such date MULTIPLIED BY the face
amount of such documentary Letter of Credit, PLUS (C) a fronting fee to the
Agent equal to one-eighth of one percent (0.125%) per annum of the face amount
of such documentary Letter of Credit, such Letter of Credit Fee (but not such
issuance, administrative or fronting fees) to be for the accounts of the Banks
in accordance with their respective Commitment Percentages.

                         5. CERTAIN GENERAL PROVISIONS.
                            --------------------------


     5.1. FEES. The Borrower agrees to pay to the Agent the fees described in
the letter dated as of the date hereof between the Agent and the Borrower (the
"Agent's Side Letter") in accordance with the terms and conditions thereof.

     5.2. FUNDS FOR PAYMENTS.
          ------------------

          5.2.1. PAYMENTS TO AGENT. All payments of principal, interest,
     Reimbursement Obligations, commitment fees, Letter of Credit Fees and any
     other amounts due hereunder or under any of the other Loan Documents shall
     be made to the Agent, for the respective accounts of the Banks and the
     Agent, at the Agent's Head Office or at such other location in the Boston,
     Massachusetts, area that the Agent may from time to time designate, in each
     case in immediately available funds.


          5.2.2. NO OFFSET, ETC. All payments by the Borrower hereunder and
     under any of the other Loan Documents shall be made without setoff or
     counterclaim and free and clear of and without deduction for any taxes,
     levies, imposts, duties, charges, fees, deductions, withholdings,
     compulsory loans, restrictions or conditions of any nature now or hereafter
     imposed or levied by any jurisdiction or any political subdivision thereof
     or taxing or other authority therein unless the Borrower is compelled by
     law to make such deduction or withholding. If any such obligation is
     imposed upon the Borrower with respect to any amount payable by it
     hereunder or under any of the other Loan Documents, the Borrower will pay
     to the Agent, for the account of the Banks or (as the case may be) the
     Agent, on the date on which such amount is due and payable hereunder or
     under such other Loan Document, such additional amount in Dollars as shall
     be necessary to enable the Banks or the Agent to receive the same net
     amount which the Banks or the Agent would have received on such due date
     had no such obligation been imposed upon the Borrower. The Borrower will
     deliver promptly to the Agent certificates or other valid vouchers for all
     taxes or other charges deducted from or paid with respect to payments made
     by the Borrower hereunder or under such other Loan Document.


<PAGE>   32
                                      -25-

     5.3. COMPUTATIONS. All computations of interest on the Loans and of
commitment fees, Letter of Credit Fees or other fees shall, unless otherwise
expressly provided herein, be based on a 360-day year and paid for the actual
number of days elapsed; PROVIDED, HOWEVER, that computations of interest on Base
Rate Loans shall be based on a 365 or, as the case may be, 366-day year and paid
for the actual number of days elapsed. Except as otherwise provided in the
definition of the term "Interest Period" with respect to Eurodollar Rate Loans,
whenever a payment hereunder or under any of the other Loan Documents becomes
due on a day that is not a Business Day, the due date for such payment shall be
extended to the next succeeding Business Day, and interest shall accrue during
such extension. The outstanding amount of the Loans as reflected on the records
on each Bank and the Agent from time to time shall be considered correct and
binding on the Borrower unless within five (5) Business Days after receipt of
any notice from the Agent or any of the Banks of such outstanding amount, the
Borrower shall notify the Agent or such Bank to the contrary.

     5.4. INABILITY TO DETERMINE EURODOLLAR RATE. In the event, prior to the
commencement of any Interest Period relating to any Eurodollar Rate Loan, the
Agent shall determine or be notified by the Majority Banks that adequate and
reasonable methods do not exist for ascertaining the Eurodollar Rate that would
otherwise determine the rate of interest to be applicable to any Eurodollar Rate
Loan during any Interest Period, the Agent shall forthwith give notice of such
determination (which shall be conclusive and binding on the Borrower and the
Banks) to the Borrower and the Banks. In such event (i) any Loan Request or
Conversion Request with respect to Eurodollar Rate Loans shall be automatically
withdrawn and shall be deemed a request for Base Rate Loans, (ii) each
Eurodollar Rate Loan will automatically, on the last day of the then current
Interest Period relating thereto, become a Base Rate Loan, and (iii) the
obligations of the Banks to make Eurodollar Rate Loans shall be suspended until
the Agent determines that the circumstances giving rise to such suspension no
longer exist, whereupon the Agent shall so notify the Borrower and the Banks.

     5.5. ILLEGALITY. Notwithstanding any other provisions herein, if any
present or future law, regulation, treaty or directive or in the interpretation
or application thereof shall make it unlawful for any Bank to make or maintain
Eurodollar Rate Loans, such Bank shall forthwith give notice of such
circumstances to the Borrower and the other Banks and thereupon (i) the
commitment of such Bank to make Eurodollar Rate Loans or convert Loans of
another Type to Eurodollar Rate Loans shall forthwith be suspended and (ii) such
Bank's Loans then outstanding as Eurodollar Rate Loans, if any, shall be
converted automatically to Base Rate Loans on the last day of each Interest
Period applicable to such Eurodollar Rate Loans or within such earlier period as
may be required by law. The Borrower hereby agrees promptly to pay the Agent for
the account of such Bank, upon demand by such Bank, any additional amounts
necessary to compensate such Bank for any costs incurred by such Bank in making
any conversion in accordance with this [Section]5.5, including any interest or
fees payable by such Bank to lenders of funds obtained by it in order to make or
maintain its Eurodollar Rate Loans hereunder. 


<PAGE>   33


                                      -26-

     5.6. ADDITIONAL COSTS, ETC.If any present or future applicable law, which
expression, as used herein, includes statutes, rules and regulations thereunder
and interpretations thereof by any competent court or by any governmental or
other regulatory body or official charged with the administration or the
interpretation thereof and requests, directives, instructions and notices at any
time or from time to time hereafter made upon or otherwise issued to any Bank or
the Agent by any central bank or other fiscal, monetary or other authority
(whether or not having the force of law), shall:

          (a) subject any Bank or the Agent to any tax, levy, impost, duty,
     charge, fee, deduction or withholding of any nature with respect to this
     Credit Agreement, the other Loan Documents, any Letters of Credit, such
     Bank's Commitment or the Loans (other than taxes based upon or measured by
     the income or profits of such Bank or the Agent), or

          (b) materially change the basis of taxation (except for changes in
     taxes on income or profits) of payments to any Bank of the principal of or
     the interest on any Loans or any other amounts payable to any Bank or the
     Agent under this Credit Agreement or any of the other Loan Documents, or

          (c) impose or increase or render applicable (other than to the extent
     specifically provided for elsewhere in this Credit Agreement) any special
     deposit, reserve, assessment, liquidity, capital adequacy or other similar
     requirements (whether or not having the force of law) against assets held
     by, or deposits in or for the account of, or loans by, or letters of credit
     issued by, or commitments of an office of any Bank, or

          (d) impose on any Bank or the Agent any other conditions or
     requirements with respect to this Credit Agreement, the other Loan
     Documents, any Letters of Credit, the Loans, such Bank's Commitment, or any
     class of loans, letters of credit or commitments of which any of the Loans
     or such Bank's Commitment forms a part, and the result of any of the
     foregoing is

               (i) to increase the cost to any Bank of making, funding, issuing,
          renewing, extending or maintaining any of the Loans or such Bank's
          Commitment or any Letter of Credit, or

               (ii) to reduce the amount of principal, interest, Reimbursement
          Obligation or other amount payable to such Bank or the Agent hereunder
          on account of such Bank's Commitment, any Letter of Credit or any of
          the Loans, or

               (iii) to require such Bank or the Agent to make any payment or to
          forego any interest or Reimbursement Obligation or other sum payable
          hereunder, the amount of which payment or foregone interest or
          Reimbursement Obligation or other sum is calculated by reference to
          the gross amount of any sum receivable






<PAGE>   34

                                      -27-

          or deemed received by such Bank or the Agent from the Borrower
          hereunder,

then, and in each such case, the Borrower will, upon demand made by such Bank or
(as the case may be) the Agent at any time and from time to time and as often as
the occasion therefor may arise, pay to such Bank or the Agent such additional
amounts as will be sufficient to compensate such Bank or the Agent for such
additional cost, reduction, payment or foregone interest or Reimbursement
Obligation or other sum.

     5.7. CAPITAL ADEQUACY. If after the date hereof any Bank or the Agent
determines that (i) the adoption of or change in any law, governmental rule,
regulation, policy, guideline or directive (whether or not having the force of
law) regarding capital requirements for banks or bank holding companies or any
change in the interpretation or application thereof by a court or governmental
authority with appropriate jurisdiction, or (ii) compliance by such Bank or the
Agent or any corporation controlling such Bank or the Agent with any law,
governmental rule, regulation, policy, guideline or directive (whether or not
having the force of law) of any such entity regarding capital adequacy, has the
effect of reducing the return on such Bank's or the Agent's commitment with
respect to any Loans to a level below that which such Bank or the Agent could
have achieved but for such adoption, change or compliance (taking into
consideration such Bank's or the Agent's then existing policies with respect to
capital adequacy and assuming full utilization of such entity's capital) by any
amount deemed by such Bank or (as the case may be) the Agent to be material,
then such Bank or the Agent may notify the Borrower of such fact. To the extent
that the amount of such reduction in the return on capital is not reflected in
the Base Rate, the Borrower agrees to pay such Bank or (as the case may be) the
Agent for the amount of such reduction in the return on capital as and when such
reduction is determined upon presentation by such Bank or (as the case may be)
the Agent of a certificate in accordance with [Section]5.8 hereof. Each Bank
shall allocate such cost increases among its customers in good faith and on an
equitable basis.

     5.8. CERTIFICATE. A certificate setting forth any additional amounts
payable pursuant to [Sections]5.6 or 5.7 and a brief explanation of such
amounts which are due, submitted by any Bank or the Agent to the Borrower, shall
be conclusive, absent manifest error, that such amounts are due and owing. The
Agent or any Bank which becomes aware that such amounts are due and owing shall
provide such Certificate to the Borrower within a reasonable period after
becoming so aware.

     5.9. INDEMNITY. The Borrower agrees to indemnify each Bank and to hold each
Bank harmless from and against any loss, cost or expense (including loss of
anticipated profits) that such Bank may sustain or incur as a consequence of (i)
default by the Borrower in payment of the principal amount of or any interest on
any Eurodollar Rate Loans as and when due and payable, including any such loss
or expense arising from interest or fees payable by such Bank to lenders of
funds obtained by it in order to maintain its Eurodollar Rate Loans,

<PAGE>   35

                                      -28-

     (ii) default by the Borrower in making a borrowing or conversion after the
Borrower has given (or is deemed to have given) a Loan Request or a Conversion
Request relating thereto in accordance with [Section]2.6 or [Section]2.7 or
(iii) the making of any payment of a Eurodollar Rate Loan or the making of any
conversion of any such Loan to a Base Rate Loan on a day that is not the last
day of the applicable Interest Period with respect thereto, including interest
or fees payable by such Bank to lenders of funds obtained by it in order to
maintain any such Loans.

     5.10. INTEREST AFTER DEFAULT.

          5.10.1. OVERDUE AMOUNTS. Overdue principal and (to the extent
     permitted by applicable law) interest on the Loans and all other overdue
     amounts payable hereunder or under any of the other Loan Documents shall
     bear interest compounded monthly and payable on demand at a rate per annum
     equal to two percent (2%) above the Base Rate until such amount shall be
     paid in full (after as well as before judgment).

          5.10.2. AMOUNTS NOT OVERDUE. During the continuance of a Default or an
     Event of Default the principal of the Loans not overdue shall, until such
     Default or Event of Default has been cured or remedied or such Default or
     Event of Default has been waived by the Majority Banks pursuant to
     [Section]26, bear interest at a rate per annum equal to the greater of (i)
     two percent (2%) above the rate of interest otherwise applicable to such
     Loans pursuant to [Section]2.5 and (ii) the rate of interest applicable to
     overdue principal pursuant to [Section]5.10.1.

                     6. GUARANTIES AND PLEDGE OF SECURITIES.
                        -----------------------------------

     The Obligations shall be guaranteed by each Guarantor pursuant to the terms
of the Guaranties; PROVIDED, HOWEVER, that until the Guaranty Delivery Date, the
Guaranty of Hadco Acquisition shall be limited to an amount equal to the Maximum
Guaranteed Loan Value. The obligations of Hadco Acquisition under its Guaranty
shall be secured by a pledge of all of the Securities owned by Hadco Acquisition
pursuant to the Stock Pledge Agreement; PROVIDED, HOWEVER, that so long as no
Default or Event of Default has occurred and is continuing, the Agent shall
release such pledge on the Guaranty Delivery Date.

                       7. REPRESENTATIONS AND WARRANTIES.
                          ------------------------------

     The Borrower represents and warrants to the Banks and the Agent as follows:

     7.1.  CORPORATE AUTHORITY.
           -------------------

          7.1.1. INCORPORATION; GOOD STANDING.Each of the Transaction Parties
     (i) is a corporation duly organized, validly existing and in good standing
     under the laws of its state of incorporation, (ii) has all requisite
     corporate power to own its property and conduct its business as now
     conducted and as presently contemplated upon the consummation of the

<PAGE>   36

                                      -29-

     Tender Offer and the Merger, and (iii) is in good standing as a foreign
     corporation and is duly authorized to do business in each jurisdiction
     where such qualification is necessary except where a failure to be so
     qualified would not have a materially adverse effect on the business,
     assets or financial condition of such Transaction Parties.

          7.1.2. AUTHORIZATION.The execution, delivery and performance of this
     Credit Agreement and the other Transaction Documents to which any of the
     Transaction Parties is or is to become a party and the transactions
     contemplated hereby and thereby (a) are within the corporate authority of
     such Person, (b) have been duly authorized by all necessary corporate
     proceedings, including, without limitation, any consents or approvals of
     shareholders of the Borrower, Hadco Acquisition or Zycon, (c) do not
     conflict with or result in any breach or contravention of any provision of
     law, statute, rule or regulation to which any of the Transaction Parties is
     subject (including, without limitation, Regulations G, T, U or X of the
     Board of Governors of the Federal Reserve System) or any judgment, order,
     writ, injunction, license or permit applicable to any of the Transaction
     Parties and (d) do not conflict with any provision of the corporate charter
     or bylaws of, or any agreement or other instrument binding upon, any of the
     Transaction Parties. The Merger is exempt from the restrictions on business
     combinations with interested stockholders set forth in [Section]203 of
     Chapter 1, Title 8 of the Delaware General Corporation law.

          7.1.3. ENFORCEABILITY. The execution and delivery of this Credit
     Agreement and the other Transaction Documents to which any of the
     Transaction Parties is or is to become a party will result in valid and
     legally binding obligations of such Person enforceable against it in
     accordance with the respective terms and provisions hereof and thereof,
     except as enforceability is limited by bankruptcy, insolvency,
     reorganization, moratorium or other laws relating to or affecting generally
     the enforcement of creditors' rights and except to the extent that
     availability of the remedy of specific performance or injunctive relief is
     subject to the discretion of the court before which any proceeding therefor
     may be brought.

     7.2. GOVERNMENTAL APPROVALS. The execution, delivery and performance by any
of the Transaction Parties of this Credit Agreement and the other Transaction
Documents to which any of the Transaction Parties is or is to become a party and
the transactions contemplated hereby and thereby do not require the approval or
consent of, or filing with, any governmental agency or authority other than
those already obtained or to be obtained in accordance with the requirements of
the Transaction Documents.

     7.3. TITLE TO PROPERTIES; LEASES.Except as indicated on SCHEDULE 7.3
hereto, the Borrower and its Subsidiaries or, as the case may be, Zycon and its
Subsidiaries, own all of the assets reflected in the consolidated balance sheet
of the Borrower and its Subsidiaries, or, as the case may be, Zycon and its

<PAGE>   37

                                      -30-

Subsidiaries as at the Balance Sheet Date or, as the case may be, the Zycon
Balance Sheet Date, or acquired since that date (except property and assets sold
or otherwise disposed of in the ordinary course of business since that date),
subject to no rights of others, including any mortgages, leases, conditional
sales agreements, title retention agreements, liens or other encumbrances except
Permitted Liens. As of the Closing Date, the Borrower and its Subsidiaries will
own all of the assets reflected in the Pro Forma Balance Sheet.

     7.4. FINANCIAL STATEMENTS, PROJECTIONS, PRO FORMA BALANCE SHEET AND
          --------------------------------------------------------------
SOLVENCY.
--------

          7.4.1. FINANCIAL STATEMENTS. There has been furnished to each of the
     Banks a consolidated balance sheet of the Borrower and its Subsidiaries as
     at the Balance Sheet Date, and a consolidated statement of income of the
     Borrower and its Subsidiaries for the fiscal year then ended, certified by
     Arthur Andersen LLP, together with a consolidated balance sheet of Zycon
     and its Subsidiaries as at the Zycon Balance Sheet Date, and a consolidated
     statement of income of Zycon and its Subsidiaries for the portion of the
     fiscal year then ended, certified by Arthur Andersen LLP. Such balance
     sheets and statements of income have been prepared in accordance with
     generally accepted accounting principles and fairly present the financial
     condition of the Borrower or Zycon, as the case may be, as at the close of
     business on the date thereof and the results of operations for the fiscal
     year then ended. There are no contingent liabilities of the Borrower or any
     of its Subsidiaries as of the Balance Sheet Date, or of Zycon and its
     Subsidiaries as of the Zycon Balance Sheet Date, involving material
     amounts, known to the officers of the Borrower, which were not disclosed in
     such balance sheets and the notes related thereto.

          7.4.2. PROJECTIONS. The projections of the annual operating budgets of
     the Borrower and its Subsidiaries following the Tender Offer and the Merger
     on a consolidated basis, balance sheets and cash flow statements for the
     1997 to 2001 fiscal years, copies of which have been delivered to each
     Bank, disclose all assumptions made with respect to general economic,
     financial and market conditions used in formulating such projections. To
     the knowledge of the Borrower or any of its Subsidiaries, no facts exist
     that (individually or in the aggregate) would result in any material change
     in any of such projections. The projections are based upon reasonable
     estimates and assumptions, have been prepared on the basis of the
     assumptions stated therein and reflect the reasonable estimates of the
     Borrower and its Subsidiaries of the results of operations and other
     information projected therein.

          7.4.3. PRO FORMA BALANCE SHEET.There will be furnished to the Agent
     and the Banks on or before the Closing Date an unaudited PRO FORMA balance
     sheet of the Borrower and its Subsidiaries as at the Closing Date, adjusted
     to give effect to the initial Loans made on the Closing Date, to the
     acquisition by Hadco Acquisition on the date thereof of the

<PAGE>   38

                                      -31-

     applicable percentage of the outstanding Securities in the Tender Offer
     (the "Pro Forma Balance Sheet") and to the Merger. The Pro Forma Balance
     Sheet presents fairly in accordance with generally accepted accounting
     principles used in connection with the preparation of historical financial
     statements the financial position of the Borrower and its Subsidiaries on a
     PRO FORMA basis and properly gives effect in accordance with generally
     accepted accounting principles used in connection with the preparation of
     historical financial statements to the application of the PRO FORMA
     adjustments to such balance sheet necessary to reflect the transactions
     contemplated in the Transaction Documents. There are no liabilities or
     contingent liabilities of the Borrower and its Subsidiaries which are
     required to be disclosed in accordance with generally accepted accounting
     principles applicable to the preparation of historical financial statements
     that will not be disclosed in the Pro Forma Balance Sheet or in the notes
     thereto.

          7.4.4. SOLVENCY. Each of the Transaction Parties, both before and
     after giving effect to the Tender Offer, the Merger and the other
     transactions contemplated hereby and by the other Transaction Documents, is
     solvent (within the meaning contemplated by Section 548 of Title 11 of the
     United States Code and any similar state statute which may be applicable),
     has and will have assets having a fair value in excess of the amount
     required to pay its probable liabilities on its existing debts as they
     become absolute and matured and has, and will have, access to adequate
     capital for the conduct of its business and the ability to pay its debts
     from time to time incurred in connection therewith as such debts mature.

     7.5. NO MATERIAL CHANGES, ETC. Except as set forth on SCHEDULE 7.5 hereto,
since the Balance Sheet Date or, as the case may be, the Zycon Balance Sheet
Date, there has occurred no materially adverse change in the financial condition
or business of the Borrower and its Subsidiaries or, as the case may be, of
Zycon and its Subsidiaries, as shown on or reflected in the consolidated balance
sheet of the Borrower and its Subsidiaries as at the Balance Sheet Date, or, as
the case may be, of Zycon and its Subsidiaries for the year then ended, or the
consolidated statements of income for the fiscal year of the Borrower or, as the
case may be, Zycon then ended, other than changes in the ordinary course of
business that have not had any materially adverse effect, either individually or
in the aggregate, on the business or financial condition of the Borrower and its
Subsidiaries, considered as a whole, or, as the case may be, Zycon and its
Subsidiaries, considered as a whole. Since the Balance Sheet Date, the Borrower
has not made any Distribution, and since the Zycon Balance Sheet Date, Zycon has
not made any Distribution.

     7.6. FRANCHISES, PATENTS, COPYRIGHTS, ETC. Each of the Transaction Parties
possesses all franchises, patents, copyrights, trademarks, trade names, licenses
and permits, and rights in respect of the foregoing, adequate for the conduct of
its business substantially as now conducted without known conflict with any
rights of others.

<PAGE>   39

                                      -32-

     7.7. LITIGATION. There is no restraining order, injunction or shareholder
derivative suit applicable to the Tender Offer or the Merger. There is, however,
one stockholder derivative suit applicable to the tender offer for Zycon,
previously made by Hicks, Muse, Tate & Furst Incorporated. Except as set forth
in SCHEDULE 7.7 hereto, there are no actions, suits, proceedings or
investigations of any kind pending or threatened against any of the Transaction
Parties, before any court, tribunal or administrative agency or board that, if
adversely determined, might, either in any case or in the aggregate, materially
adversely affect the properties, assets, financial condition or business of the
Transaction Parties, considered as a whole, or materially impair the right of
the Transaction Parties, considered as a whole, to carry on business
substantially as now conducted by them, or result in any substantial liability
not adequately covered by insurance, or for which adequate reserves are not
maintained on the consolidated balance sheet of the Borrower and its
Subsidiaries, or which question the validity of this Credit Agreement or any of
the other Transaction Documents, or any action taken or to be taken pursuant
hereto or thereto (including the consummation of the Tender Offer and the
Merger).

     7.8. NO MATERIALLY ADVERSE CONTRACTS, ETC. None of the Transaction Parties
is subject to any charter, corporate or other legal restriction, or any
judgment, decree, order, rule or regulation that has or is expected in the
future to have a materially adverse effect on the business, assets or financial
condition of such Transaction Party or on such Transaction Party's ability to
perform its obligations under the Loan Documents and the other Transaction
Documents to which it is a party. Except as set forth on SCHEDULE 7.5 hereto,
none of the Transaction Parties is a party to any contract or agreement that has
or is expected, in the judgment of the Borrower's officers, to have any
materially adverse effect on the business of such Transaction Party.

     7.9. COMPLIANCE WITH OTHER INSTRUMENTS, LAWS, ETC. None of the Transaction
Parties is in violation of any provision of its charter documents, bylaws, or
any agreement or instrument to which it may be subject or by which it or any of
its properties may be bound or any decree, order, judgment, statute, license,
rule or regulation, in any of the foregoing cases in a manner that could, except
as otherwise set forth on SCHEDULE 7.17, result in the imposition of substantial
penalties or materially and adversely affect the financial condition, properties
or business of such Transaction Party.

     7.10. TAX STATUS. The Transaction Parties (a) except as set forth in
SCHEDULE 7.10 hereto, have made or filed all federal and state income and all
other tax returns, reports and declarations required by any jurisdiction to
which any of them is subject, (b) have paid all taxes and other governmental
assessments and charges shown or determined to be due on such returns, reports
and declarations, except those being contested in good faith and by appropriate
proceedings and (c) have set aside on their books provisions reasonably adequate
for the payment of all taxes for periods subsequent to the periods to which such
returns, reports or declarations apply. There are no unpaid taxes in any
material amount claimed to be due by the taxing authority of any jurisdiction,
and the officers of the Borrower know of no basis for any such claim. None of
the

<PAGE>   40

                                      -33-

Transaction Parties has consented or will consent to be treated as a "consenting
corporation" as defined in Section 341 of the Code.

     7.11. NO EVENT OF DEFAULT. No Default or Event of Default has occurred and
is continuing. No default has occurred and is continuing under any of the
Transaction Documents, and no accrued right of rescission, cancellation or
termination exists under any of the Transaction Documents. To the best of the
Borrower's knowledge, no default has occurred and is continuing under any
agreement concerning Indebtedness of Zycon or any of its Subsidiaries.

     7.12.HOLDING COMPANY AND INVESTMENT COMPANY ACTS. None of the Transaction
Parties is a "holding company", or a "subsidiary company" of a "holding
company", or an affiliate" of a "holding company", as such terms are defined in
the Public Utility Holding Company Act of 1935; nor is it an "investment
company", or an "affiliated company" or a "principal underwriter" of an
"investment company", as such terms are defined in the Investment Company Act of
1940.

     7.13. ABSENCE OF FINANCING STATEMENTS; PERFECTION OF SECURITY INTEREST.
Except with respect to Permitted Liens, there is no financing statement,
security agreement, chattel mortgage, real estate mortgage or other document
filed or recorded with any filing records, registry or other public office, that
purports to cover, affect or give notice of any present or possible future lien
on, or security interest in, any assets or property of any of the Transaction
Parties or any rights relating thereto. Upon the consummation of the Tender
Offer and except as otherwise contemplated by [Section]8.16, all deposits of the
Securities and all other actions shall have been taken that are necessary or
advisable, under applicable law, to establish and perfect the Agent's security
interest in the Securities, and the Securities and the Agent's rights with
respect to the Securities will not be subject to any setoff, claims,
withholdings or other defenses. Upon the consummation of the Tender Offer, Hadco
Acquisition will be the owner of the Securities, free from any lien, security
interest, encumbrance and any other claim or demand.

     7.14. CERTAIN TRANSACTIONS. Except for arm's length transactions pursuant
to which any of the Transaction Parties makes payments in the ordinary course of
business upon terms no less favorable than any of the Transaction Parties could
obtain from third parties, none of the officers, directors, or employees of any
of the Transaction Parties is presently a party to any transaction with any of
the Transaction Parties (other than for services as employees, officers and
directors), including any contract, agreement or other arrangement providing for
the furnishing of services to or by, providing for rental of real or personal
property to or from, or otherwise requiring payments to or from any officer,
director or such employee or, to the knowledge of the Borrower, any corporation,
partnership, trust or other entity in which any officer, director, or any such
employee has a substantial interest or is an officer, director, trustee or
partner.

     7.15.  EMPLOYEE BENEFIT PLANS.

<PAGE>   41
                                     -34-

          7.15.1. IN GENERAL. Each Employee Benefit Plan and each Guaranteed
     Pension Plan has been maintained and operated in compliance in all material
     respects with the provisions of ERISA and, to the extent applicable, the
     Code, including but not limited to the provisions thereunder respecting
     prohibited transactions and the bonding of fiduciaries and other persons
     handling plan funds as required by [Section]412 of ERISA. The Borrower has
     heretofore delivered to the Agent the most recently completed annual
     report, Form 5500, with all required attachments, and actuarial statement
     required to be submitted under [Section]103(d) of ERISA, with respect to
     each Guaranteed Pension Plan.

          7.15.2. TERMINABILITY OF WELFARE PLANS. No Employee Benefit Plan which
     is an employee welfare benefit plan within the meaning of [Section]3(1) or
     [Section]3(2)(B) of ERISA provides benefit coverage subsequent to
     termination of employment except as required by Title I, Part 6 of ERISA or
     applicable state insurance laws. The Borrower or, as the case may be, Zycon
     may terminate each such Plan at any time (or at any time subsequent to the
     expiration of any applicable bargaining agreement) in the discretion of the
     Borrower or Zycon without liability to any Person other than for claims
     arising prior to termination.

          7.15.3. GAURANTEED PENSION PLANS. Each contribution required to be
     made to a Guaranteed Pension Plan, whether required to be made to avoid the
     incurrence of an accumulated funding deficiency, the notice or lien
     provisions of [Section]302(f) of ERISA, or otherwise, has been timely made.
     No waiver of an accumulated funding deficiency or extension of amortization
     periods has been received with respect to any Guaranteed Pension Plan, and
     neither the Borrower nor any ERISA Affiliate is obligated to or has posted
     security in connection with an amendment of a Guaranteed Pension Plan
     pursuant to [Section]307 of ERISA or [Section]401(a)(29) of the Code. No
     liability to the PBGC (other than required insurance premiums, all of which
     have been paid) has been incurred by the Borrower or any ERISA Affiliate
     with respect to any Guaranteed Pension Plan and there has not been any
     ERISA Reportable Event, or any other event or condition which presents a
     material risk of termination of any Guaranteed Pension Plan by the PBGC.
     Based on the latest valuation of each Guaranteed Pension Plan (which in
     each case occurred within twelve months of the date of this
     representation), and on the actuarial methods and assumptions employed for
     that valuation, the aggregate benefit liabilities of all such Guaranteed
     Pension Plans within the meaning of [Section]4001 of ERISA did not exceed
     the aggregate value of the assets of all such Guaranteed Pension Plans,
     disregarding for this purpose the benefit liabilities and assets of any
     Guaranteed Pension Plan with assets in excess of benefit liabilities.

          7.15.4. MULTIEMPLOYER PLANS. None of the Borrower, Zycon or any ERISA
     Affiliate has incurred any material liability (including secondary
     liability) to any Multiemployer Plan as a result of a complete or partial
     withdrawal from such Multiemployer Plan under [Section]4201 of ERISA
<PAGE>   42

                                      -35-

     or as a result of a sale of assets described in [Section]4204 of ERISA.
     None of the Borrower, Zycon or any ERISA Affiliate has been notified that
     any Multiemployer Plan is in reorganization or insolvent under and within
     the meaning of [Section]4241 or [Section]4245 of ERISA or is at risk of
     entering reorganization or becoming insolvent, or that any Multiemployer
     Plan intends to terminate or has been terminated under [Section]4041A of
     ERISA.

     7.16. USE OF PROCEEDS. The proceeds of the Loans shall be used for purchase
of the Securities pursuant to the terms of the Tender Offer Documents, for
refinancing of existing indebtedness of the Borrower to FNBB and of Zycon to
Comerica Bank-California, Comerica Bank-Detroit and/or any of their affiliates,
and for and . The Borrower will obtain Letters of Credit solely for general
corporate purposes. No portion of any Loan is to be used, and no portion of any
Letter of Credit is to be obtained, for the purpose of purchasing or carrying
any Margin Stock, except in compliance with such Regulations.

     7.17. ENVIRONMENTAL COMPLIANCE. The Borrower has taken all reasonable steps
to investigate the past and present condition and usage of the Real Estate and
the operations conducted thereon and, except as set forth in SCHEDULE 7.17
attached hereto, has determined that:

          (a) none of the Transaction Parties or any operator of the Real Estate
     or any operations thereon is in violation, or alleged violation, of any
     judgment, decree, order, law, license, rule or regulation pertaining to
     environmental matters, including without limitation, those arising under
     the Resource Conservation and Recovery Act ("RCRA"), the Comprehensive
     Environmental Response, Compensation and Liability Act of 1980 as amended
     ("CERCLA"), the Superfund Amendments and Reauthorization Act of 1986
     ("SARA"), the Federal Clean Water Act, the Federal Clean Air Act, the Toxic
     Substances Control Act, or any state or local statute, regulation,
     ordinance, order or decree relating to health, safety or the environment
     (hereinafter "Environmental Laws"), which violation would have a material
     adverse effect on the business, assets or financial condition of the
     Transaction Parties, considered as a whole;

          (b) none of the Transaction Parties has received notice from any third
     party including, without limitation, any federal, state or local
     governmental authority, (i) that any one of them has been identified by the
     United States Environmental Protection Agency ("EPA") as a potentially
     responsible party under CERCLA with respect to a site listed on the
     National Priorities List, 40 C.F.R. Part 300 Appendix B; (ii) that any
     hazardous waste, as defined by 42 U.S.C. [Section]6903(5), any hazardous
     substances as defined by 42 U.S.C. [Section]9601(14), any pollutant or
     contaminant as defined by 42 U.S.C. [Section]9601(33) and any toxic
     substances, oil or hazardous materials or other chemicals or substances
     regulated by any Environmental Laws ("Hazardous Substances") which any one
     of them has generated, transported or disposed of has been found at any
     site at which a federal, state or local agency or other third party has
     conducted or has ordered that the Transaction Parties conduct a remedial
     investigation, removal or other response action pursuant to any
     Environmental Law; or (iii) that it is or shall be a named party to any

<PAGE>   43

                                      -36-

     claim, action, cause of action, complaint, or legal or administrative
     proceeding (in each case, contingent or otherwise) arising out of any third
     party's incurrence of costs, expenses, losses or damages of any kind
     whatsoever in connection with the release of Hazardous Substances;

          (c) except to the extent that any of the following would not have a
     material adverse effect on the value of the Real Estate or the business,
     assets or financial condition of the Transaction Parties, considered as a
     whole: (i) no portion of the Real Estate has been used for the handling,
     processing, storage or disposal of Hazardous Substances except in
     accordance with applicable Environmental Laws; and no underground tank or
     other underground storage receptacle for Hazardous Substances is located on
     any portion of the Real Estate; (ii) in the course of any activities
     conducted by and of the Transaction Parties or operators of its or their
     properties, no Hazardous Substances have been generated or are being used
     on the Real Estate except in accordance with applicable Environmental Laws;
     (iii) there have been no releases (i.e. any past or present releasing,
     spilling, leaking, pumping, pouring, emitting, emptying, discharging,
     injecting, escaping, disposing or dumping) or threatened releases of
     Hazardous Substances on, upon, into or from the properties of the
     Transaction Parties; (iv) to the best of the Borrower's knowledge, there
     have been no releases on, upon, from or into any real property in the
     vicinity of any of the Real Estate which, through soil or groundwater
     contamination, may have come to be located on the Real Estate; and (v) in
     addition, any Hazardous Substances that have been generated on any of the
     Real Estate have been transported offsite only by carriers having an
     identification number issued by the EPA or by carriers not required by law
     to have such identification numbers, treated or disposed of only by
     treatment, recycling or disposal facilities maintaining valid permits as
     required under applicable Environmental Laws, which transporters and
     facilities have been and are, to the best of the Borrower's knowledge,
     operating in compliance with such permits and applicable Environmental
     Laws; and

          (d) Except with respect to matters that would not have a material
     adverse effect on the value of the Real Estate or the business, assets or
     financial condition of the Transaction Parties, considered as a whole, none
     of the Transaction Parties or any of the Real Estate is subject to any
     applicable environmental law requiring the performance of Hazardous
     Substances site assessments, or the removal or remediation of Hazardous
     Substances, or the giving of notice to any governmental agency or the
     recording or delivery to other Persons of an environmental disclosure
     document or statement by virtue of the transactions set forth herein and
     contemplated hereby, or as a condition to the effectiveness of any of the
     transactions contemplated hereby or the other Transaction Documents.

     7.18. SUBSIDIARIES, ETC. Prior to the consummation of the transactions
contemplated by the Tender Offer Documents and the Merger Documents, Hadco FSC
and Hadco Acquisition are the only Subsidiaries of the Borrower, and Zycon

<PAGE>   44
                                     -37-

Alternate Circuits, Inc., a Delaware corporation, and Zycon Corp. SDN BHD, a
Malaysian corporation, are the only Subsidiaries of Zycon. Following the
consummation of the transactions contemplated by the Tender Offer Documents and
the Merger Documents, Hadco FSC and Hadco Acquisition are the only direct
Subsidiaries of the Borrower and Zycon Alternate Circuits, Inc., a Delaware
Corporation and Zycon Corp. SDN BHD are the only Subsidiaries of Hadco
Acquisition. Except as set forth on SCHEDULE 7.18 hereto, none of the
Transaction Parties is engaged in any joint venture or partnership with any
other Person.

     7.19. MERGER AND TENDER OFFER. Each of the representations and warranties
made by the Borrower and Hadco Acquisition and, to the best of the Borrower's
knowledge, Zycon and its Subsidiaries, in any of the Merger Documents or the
Tender Offer Documents was true and correct in all material respects on the
Closing Date. SCHEDULE 7.19 sets forth a complete list of the Merger Documents
and the Tender Offer Documents, and the Borrower represents and warrants that
neither the Merger Documents nor the Tender Offer Documents have been modified,
amended or supplemented. The Borrower has delivered to the Agent and the Banks
true, complete and correct copies of the Merger Documents and the Tender Offer
Documents.

     7.20. DISCLOSURE. The representations and warranties made by the
Transaction Parties in this Credit Agreement or in any agreement, instrument,
document, certificate, statement or letter furnished to the Banks on behalf of
any of the Transaction Parties in connection with the transactions contemplated
by the Loan Documents or the other Transaction Documents do not, taken as a
whole, together with all other information provided by the Borrower in
connection with the transactions contemplated by the Transaction Documents,
contain any untrue statement of a material fact or omit to state a material fact
necessary in order to make the statements contained herein or therein not
misleading. There is no fact known to the Borrower which materially adversely
affects, or which is likely in the future to materially adversely affect, the
business, assets or financial condition of the Transaction Parties, taken as a
whole.

                    8. AFFIRMATIVE COVENANTS OF THE BORROWER.
                       -------------------------------------

     The Borrower covenants and agrees that, so long as any Loan, Unpaid
Reimbursement Obligation, Letter of Credit or Note is outstanding or any Bank
has any obligation to make any Loans or the Agent has any obligation to issue,
extend or renew any Letters of Credit:

     8.1. PUNCTUAL PAYMENT. The Borrower will duly and punctually pay or cause
to be paid the principal and interest on the Loans, all Reimbursement
Obligations, the Letter of Credit Fees, the commitment fees, the Agent's fee and
all other amounts provided for in this Credit Agreement and the other Loan
Documents to which any of the Transaction Parties is a party, all in accordance
with the terms of this Credit Agreement and such other Loan Documents.

<PAGE>   45

                                      -38-

     8.2. MAINTENANCE OF OFFICE. The Borrower will maintain its chief executive
office in Salem, New Hampshire, or at such other place in the United States of
America as the Borrower shall designate upon written notice to the Agent, where
notices, presentations and demands to or upon the Borrower in respect of the
Loan Documents to which the Borrower is a party may be given or made.

     8.3. RECORDS AND ACCOUNTS. The Borrower will (i) keep, and cause each of
the other Transaction Parties to keep, true and accurate records and books of
account in which full, true and correct entries will be made in accordance with
generally accepted accounting principles and (ii) maintain adequate accounts and
reserves for all taxes (including income taxes), depreciation, depletion,
obsolescence and amortization of its properties and the properties of the other
Transaction Parties, contingencies, and other reserves.

     8.4. FINANCIAL STATEMENTS, CERTIFICATES AND INFORMATION. The Borrower will
deliver to each of the Banks:

          (a) as soon as practicable, but in any event not later than ninety
     (90) days after the end of each fiscal year of the Borrower, the
     consolidated balance sheet of the Borrower and its Subsidiaries and the
     consolidating balance sheet of the Borrower and its Subsidiaries, each as
     at the end of such year, and the related consolidated statement of income
     and consolidated statement of cash flow and consolidating statement of
     income and consolidating statement of cash flow for such year, each setting
     forth in comparative form the figures for the previous fiscal year and all
     such consolidated and consolidating statements to be in reasonable detail,
     prepared in accordance with generally accepted accounting principles, and
     certified without qualification by Arthur Andersen LLP or by other
     independent certified public accountants satisfactory to the Agent,
     together with a written statement from such accountants to the effect that
     they have read a copy of this Credit Agreement, and that, in making the
     examination necessary to said certification, they have obtained no
     knowledge of any Default or Event of Default, or, if such accountants shall
     have obtained knowledge of any then existing Default or Event of Default
     they shall disclose in such statement any such Default or Event of Default;
     PROVIDED that such accountants shall not be liable to the Banks for failure
     to obtain knowledge of any Default or Event of Default;

          (b) as soon as practicable, but in any event not later than forty-five
     (45) days after the end of each of the fiscal quarters of the Borrower,
     copies of the unaudited consolidated balance sheet of the Borrower and its
     Subsidiaries and the unaudited consolidating balance sheet of the Borrower
     and its Subsidiaries, each as at the end of such quarter, and the related
     consolidated statement of income and consolidated statement of cash flow
     and consolidating statement of income and consolidating statement of cash
     flow for the portion of the Borrower's fiscal year then elapsed, all in
     reasonable detail and prepared in accordance with

<PAGE>   46

                                      -39-

     generally accepted accounting principles, together with a certification by
     the principal financial or accounting officer of the Borrower that the
     information contained in such financial statements fairly presents the
     financial position of the Borrower and its Subsidiaries on the date thereof
     (subject to year-end adjustments);

          (c) simultaneously with the delivery of the financial statements
     referred to in subsections (a) and (b) above, a statement certified by the
     principal financial or accounting officer of the Borrower in substantially
     the form of EXHIBIT C hereto and setting forth in reasonable detail
     computations evidencing compliance with the covenants contained in
     [Section]10 and (if applicable) reconciliations to reflect changes in
     generally accepted accounting principles since the Balance Sheet Date;

          (d) contemporaneously with the filing or mailing thereof, copies of
     all material of a financial nature, all reports, proxy statements and
     notices filed any of the Transaction Parties with the Securities and
     Exchange Commission or sent to the stockholders of the Borrower;

          (e) from time to time upon request of the Agent, projections of the
     Borrower and its Subsidiaries updating those projections delivered to the
     Banks and referred to in [Section]7.4.2 or, if applicable, updating any
     later such projections delivered in response to a request pursuant to this
     [Section]8.4(e); and

          (f) from time to time such other financial data and information
     (including accountants management letters) regarding the financial and
     other affairs of the Borrower and its Subsidiaries as the Agent or any Bank
     may reasonably request.

     8.5. NOTICES.
          -------
          8.5.1. DEFAULTS. The Borrower will promptly notify the Agent and each
     of the Banks in writing of the occurrence of any Default or Event of
     Default. If any Person shall give any notice or take any other action in
     respect of a claimed default (whether or not constituting an Event of
     Default) under this Credit Agreement or any other note, evidence of
     indebtedness, indenture or other obligation to which or with respect to
     which the Borrower or any of the other Transaction Parties is a party or
     obligor, whether as principal, guarantor, surety or otherwise, the Borrower
     shall forthwith give written notice thereof to the Agent and each of the
     Banks, describing the notice or action and the nature of the claimed
     default.

          8.5.2. ENVIRONMENTAL EVENTS. The Borrower will promptly give notice to
     the Agent and each of the Banks (i) of any violation of any Environmental
     Law that the Borrower or any of the other Transaction Parties reports in
     writing or is reportable by such Person in writing (or for which any
     written report supplemental to any oral report is made) to any federal,
     state or local environmental agency and (ii) upon becoming

<PAGE>   47

                                      -40-

     aware thereof, of any inquiry, proceeding, investigation, or other action,
     including a notice from any agency of potential environmental liability, of
     any federal, state or local environmental agency or board, that has the
     potential to materially affect the assets, liabilities, financial
     conditions or operations of the Borrower and any of the other Transaction
     Parties, considered as a whole, or the Agent's security interest pursuant
     to the Stock Pledge Agreement.

          8.5.3. NOTICE OF LITIGATION AND JUDGEMENTS. The Borrower will, and
     will cause each of the other Transaction Parties to, give notice to the
     Agent and each of the Banks in writing within fifteen (15) days of becoming
     aware of any restraining order or injunction applicable to the Tender Offer
     or the Merger or any litigation or proceedings threatened in writing or any
     pending litigation and proceedings affecting the Borrower or any of the
     other Transaction Parties or to which the Borrower or any of the other
     Transaction Parties is or becomes a party (including, without limitation,
     any shareholder derivative suit) that could reasonably be expected to have
     a material adverse effect upon the consummation of the Tender Offer or
     Merger or involving an uninsured claim against the Borrower or any of the
     other Transaction Parties that could reasonably be expected to have a
     materially adverse effect on the Borrower or any of the other Transaction
     Parties and stating the nature and status of such litigation or
     proceedings. The Borrower will, and will cause each of the other
     Transaction Parties to, give notice to the Agent and each of the Banks, in
     writing, in form and detail satisfactory to the Agent, within ten (10) days
     of any judgment not covered by insurance, final or otherwise, against the
     Borrower or any of the other Transaction Parties in an amount in excess of
     $5,000,000.

          8.5.4. NOTIFICATION OF CLAIMS AGAINST SECURITIES. For so long as the
     Stock Pledge Agreement is in s. effect, the Borrower will, immediately upon
     becoming aware thereof, notify the Agent and each of the Banks in writing
     of any setoff, claims, withholdings or other defenses to which any of the
     Securities, or the Agent's rights with respect to the Securities, are
     subject.

     8.6. CORPORATE EXISTENCE; MAINTENANCE OF PROPERTIES. Except as otherwise
required to effect the Merger, the Borrower will do or cause to be done all
things necessary to preserve and keep in full force and effect its corporate
existence, rights and franchises and those of the other Transaction Parties and
will not, and will not cause or permit any of the other Transaction Parties to,
convert to a limited liability company or limited liability partnership. The
Borrower (i) will cause all of its properties and those of the other Transaction
Parties used or useful in the conduct of its business or the business of the
other Transaction Parties to be maintained and kept in good condition, repair
and working order and supplied with all necessary equipment, (ii) will cause to
be made all necessary repairs, renewals, replacements, betterments and
improvements thereof, all as in the judgment of the Borrower may be necessary

<PAGE>   48

                                      -41-

so that the business carried on in connection therewith may be properly and
advantageously conducted at all times, and (iii) will, and will cause each of
the other Transaction Parties to, continue to engage primarily in the businesses
now conducted by them and in related businesses; PROVIDED that nothing in this
[Section]8.6 shall prevent the Borrower from discontinuing the operation and
maintenance of any of its properties or any of those of the other Transaction
Parties if such discontinuance is, in the judgment of the Borrower, desirable in
the conduct of its or their business and that do not in the aggregate materially
adversely affect the business of the Borrower and the other Transaction Parties,
considered as a whole.

     8.7. INSURANCE. The Borrower will, and will cause each of the other
Transaction Parties to, maintain with financially sound and reputable insurers
insurance with respect to its properties and business against such casualties
and contingencies as shall be in accordance with the general practices of
businesses engaged in similar activities in similar geographic areas and in
amounts, containing such terms, in such forms and for such periods as may be
reasonable and prudent and in accordance with the terms hereof.

     8.8. TAXES. The Borrower will, and will cause each of the other Transaction
Parties to, duly pay and discharge, or cause to be paid and discharged, before
the same shall become overdue, all taxes, assessments and other governmental
charges imposed upon it and its real properties, sales and activities, or any
part thereof, or upon the income or profits therefrom, as well as all claims for
labor, materials, or supplies that if unpaid might by law become a lien or
charge upon any of its property; PROVIDED that any such tax, assessment, charge,
levy or claim need not be paid if the validity or amount thereof shall currently
be contested in good faith by appropriate proceedings and if the Borrower or
such other Transaction Party shall have set aside on its books adequate reserves
with respect thereto; and PROVIDED FURTHER that the Borrower and each other
Transaction Party will pay all such taxes, assessments, charges, levies or
claims forthwith upon the commencement of proceedings to foreclose any lien that
may have attached as security therefor.

     8.9. INSPECTION OF PROPERTIES AND BOOKS, ETC.
          ---------------------------------------

          8.9.1. GENERAL. The Borrower shall permit the Banks, through the Agent
     or any of the Banks' other designated representatives, to visit and inspect
     any of the properties of the Borrower or any of the other Transaction
     Parties, to conduct commercial finance examinations of the Borrower and the
     other Transaction Parties, to examine the books of account of the Borrower
     and the other Transaction Parties (and to make copies thereof and extracts
     therefrom), and to discuss the affairs, finances and accounts of the
     Borrower and the other Transaction Parties with, and to be advised as to
     the same by, its and their officers, all at such reasonable times and
     intervals as the Agent or any Bank may reasonably request.

<PAGE>   49

                                      -42-

          8.9.2. COMMUNICATIONS WITH ACCOUNTANTS. The Borrower authorizes the
     Agent and, if accompanied by the Agent, the Banks to communicate directly
     with the Borrower's independent certified public accountants and authorizes
     such accountants to disclose to the Agent and the Banks any and all
     financial statements and other supporting financial documents and schedules
     including copies of any management letter with respect to the business,
     financial condition and other affairs of the Borrower or any of the other
     Transaction Parties. At the request of the Agent, the Borrower shall
     deliver a letter addressed to such accountants instructing them to comply
     with the provisions of this [Section]8.9.2.

     8.10. COMPLIANCE WITH LAWS, CONTRACTS, LICENSES, AND PERMITS. The Borrower
will, and will cause each of the other Transaction Parties to, comply with (i)
in all material respects, the applicable laws and regulations wherever its
business is conducted, including all Environmental Laws, (ii) the provisions of
its charter documents and by-laws, (iii) all agreements and instruments by which
it or any of its properties may be bound and (iv) all applicable decrees,
orders, and judgments. If any authorization, consent, approval, permit or
license from any officer, agency or instrumentality of any government shall
become necessary or required in order that the Borrower or any of the other
Transaction Parties may fulfill any of its obligations hereunder or any of the
other Transaction Documents to which the Borrower or such other Transaction
Party is a party, the Borrower will, or (as the case may be) will cause such
other Transaction Party to, immediately take or cause to be taken all reasonable
steps within the power of the Borrower or such other Transaction Party to obtain
such authorization, consent, approval, permit or license and furnish the Agent
and the Banks with evidence thereof.

     8.11. EMPLOYEE BENEFIT PLANS. The Borrower will (i) promptly upon request
of the Agent, furnish to the Agent a copy of the most recent actuarial statement
required to be submitted under [Section]103(d) of ERISA and Annual Report, Form
5500, with all required attachments, in respect of each Guaranteed Pension Plan
and (ii) promptly upon receipt or dispatch, furnish to the Agent any notice,
report or demand sent or received in respect of a Guaranteed Pension Plan under
[Sections]302, 4041, 4042, 4043, 4063, 4065, 4066 and 4068 of ERISA, or in
respect of a Multiemployer Plan, under [Sections]4041A, 4202, 4219, 4242, or
4245 of ERISA.

     8.12. USE OF PROCEEDS. The Borrower will use the proceeds of the Loans
solely for purchase of the Securities pursuant to the terms of the Tender Offer
Documents, for refinancing of existing indebtedness of the Borrower to FNBB and
of Zycon to Comerica Bank - California, Comerica Bank - Detroit and/or any of
their affiliates and for working capital and general corporate purposes. The
Borrower will obtain Letters of Credit solely for general corporate purposes.

     8.13. INTEREST RATE PROTECTION AGREEMENTS. Within one hundred twenty (120)
days following the Closing Date, the Borrower shall enter into and shall
maintain interest rate protection agreements with a minimum notional

<PAGE>   50

                                      -43-

amount of $75,000,000 and upon terms and conditions satisfactory in form and
substance to the Agent; PROVIDED, HOWEVER, that so long as no Default or Event
of Default shall have occurred and then be continuing, the Borrower may
terminate such interest rate protection arrangements upon the first anniversary
of the Closing Date; and PROVIDED FURTHER that, in the event that the Borrower
incurs Indebtedness permitted by [Section]9.1(k), which Indebtedness bears
interest at a fixed, rather than a floating, rate, the Borrower shall maintain
such interest rate protection arrangements with respect to a minimum notional
amount equal to the difference of $75,000,000 MINUS the amount of such permitted
fixed rate Indebtedness.

     8.14. CONFIRMATION OF GUARANTY; ADDITIONAL GUARANTIES. Immediately
following the consummation of the Merger, the Borrower shall cause Hadco
Acquisition to execute and deliver to the Agent a confirmation, in form and
substance satisfactory to the Agent, of the Guaranty to which Hadco Acquisition
is a party, ratifying the obligations of Hadco Acquisition under such Guaranty
following the consummation of the Merger and confirming that the amount of such
obligations (a) equal the total amount of the Obligations, and (b) are no longer
limited to the Maximum Guaranteed Loan Value. Immediately following the Merger,
the Borrower shall cause Zycon Alternate Circuits, Inc. to execute and deliver
to the Agent a Guaranty in the form of EXHIBIT E-1 hereto, together with such
evidence of corporate authorization, legal opinions and other documentation as
the Agent may request.

     8.15. CONSUMMATION OF MERGER. The Borrower will take, and will cause the
other Transaction Parties to take, all corporate and legal actions advisable or
necessary to cause the Merger to be approved and effected in accordance with the
Merger Documents and applicable law within sixty (60) days after the Closing
Date.

     8.16. DELIVERY OF SECURITIES. In the event that the Stock Pledge Agreement
is then still in effect, the Borrower shall, within nine (9) days following the
Closing Date, cause Hadco Acquisition to deliver stock certificates representing
each of the Securities purchased by Hadco Acquisition in connection with the
Tender Offer, together with blank stock powers, duly executed in blank, and to
take such other actions as are necessary or desirable in the opinion of the
Agent to protect and preserve its security interest in the Securities.
Immediately following any subsequent purchase of Securities for so long as the
Stock Pledge Agreement remains in effect, the Borrower shall cause Hadco
Acquisition to deliver to the Agent stock certificates representing such
additional Securities, together with undated stock powers, duly executed in
blank.

     8.17. FURTHER ASSURANCES. The Borrower will, and will cause each of the
other Transaction Parties to, cooperate with the Banks and the Agent and execute
such further instruments and documents as the Banks or the Agent shall
reasonably request to carry out to their satisfaction the transactions
contemplated by this Credit Agreement and the other Transaction Documents.

<PAGE>   51

                                      -44-

     8.18. POST-CLOSING UNDERTAKINGS. The Borrower shall, and shall cause the
other Transaction Parties to, complete or cause the completion of, all of the
conditions, actions and items set forth on SCHEDULE 8.18 on or before the
respective due dates therefor set forth on SCHEDULE 8.18.

                 9. CERTAIN NEGATIVE COVENANTS OF THE BORROWER.
                    ------------------------------------------

     The Borrower covenants and agrees that, so long as any Loan, Unpaid
Reimbursement Obligation, Letter of Credit or Note is outstanding or any Bank
has any obligation to make any Loans or the Agent has any obligations to issue,
extend or renew any Letters of Credit:

     9.1. RESTRICTIONS ON INDEBTEDNESS. The Borrower will not, and will not
permit any of the other Transaction Parties to, create, incur, assume, guarantee
or be or remain liable, contingently or otherwise, with respect to any
Indebtedness other than:

          (a) Indebtedness to the Banks and the Agent arising under any of the
     Loan Documents;

          (b) current liabilities of the Borrower or such other Transaction
     Parties incurred in the ordinary course of business not incurred through
     (i) the borrowing of money, or (ii) the obtaining of credit except for
     credit on an open account basis customarily extended and in fact extended
     in connection with normal purchases of goods and services;

          (c) Indebtedness in respect of taxes, assessments, governmental
     charges or levies and claims for labor, materials and supplies to the
     extent that payment therefor shall not at the time be required to be made
     in accordance with the provisions of [Section]8.8;

          (d) Indebtedness in respect of judgments or awards that have been in
     force for less than the applicable period for taking an appeal so long as
     execution is not levied thereunder or in respect of which the Borrower or
     such other Transaction Party shall at the time in good faith be prosecuting
     an appeal or proceedings for review and in respect of which a stay of
     execution shall have been obtained pending such appeal or review;

          (e) endorsements for collection, deposit or negotiation and warranties
     of products or services, in each case incurred in the ordinary course of
     business;

          (f) obligations under Capitalized Leases which, when combined with
     amounts outstanding under [Section]9.1(g), do not exceed $25,000,000 in
     aggregate amount at any time outstanding;

          (g) Indebtedness incurred in connection with the acquisition after the
     date hereof of any real or personal property by the Borrower or such other
     Transaction Party, PROVIDED that the aggregate principal amount of

<PAGE>   52

                                      -45-

     such Indebtedness of the Borrower and the other Transaction Parties shall,
     when combined with amounts outstanding under [Section]9.1(f) not exceed the
     aggregate amount of $25,000,000 at any one time;

          (h) Indebtedness of the Borrower and the other Transaction Parties
     existing on the date hereof and listed and described on SCHEDULE 9.1
     hereto;

          (i) Indebtedness of (i) a Guarantor, following its execution and
     delivery of its Guaranty to the Agent, to the Borrower (including
     Indebtedness of Hadco Acquisition to the Borrower, the proceeds of which
     are to be used to purchase the Securities pursuant to the Tender Offer
     Documents); (ii) Hadco FSC to the Borrower, in an aggregate amount not to
     exceed $2,000,000; (iii) Zycon to the Borrower to the extent required by
     the Bank Bumiputra Loan Agreement, but not to exceed $5,000,000 in the
     aggregate; (iv) from and after the Closing Date, Zycon Corp. SDN BHD to the
     Borrower or Hadco Acquisition in an aggregate amount not to exceed
     $55,000,000, no more than $11,000,000 of which may be incurred in any one
     fiscal year of the Borrower; PROVIDED, HOWEVER, that if during any fiscal
     year the amount of such Indebtedness permitted for that fiscal year is not
     so utilized, such unutilized amount may be utilized in the next succeeding
     fiscal year; and (v) until the Guaranty Delivery Date, Zycon or Zycon
     Alternate Circuits, Inc. to the Borrower or Hadco Acquisition in an
     aggregate amount not to exceed $25,000,000;

          (j) Indebtedness consisting of contingent obligations arising in
     connection with any Transaction Party's compliance with applicable
     Environmental Laws in an amount not to exceed in the aggregate, ten percent
     (10%) of Consolidated Net Worth;

          (k) So long as no Default or Event of Default shall have occurred and
     be continuing or would occur following the incurrence of any thereof,
     unsecured Indebtedness of the Borrower or any of its Subsidiaries in an
     aggregate amount not to exceed $175,000,000, consisting of (i) up to
     $150,000,000 (but not to exceed, when combined with amounts of Indebtedness
     incurred pursuant to clause (ii) of this [Section]9.1(k), $175,000,000)
     which is expressly subordinated and made junior to the payment and
     performance in full of the Obligations on terms and conditions satisfactory
     to the Agent and the Majority Banks in their sole and absolute discretion,
     and evidenced as subordinate by a Subordination and Intercreditor Agreement
     or another written instrument containing subordination provisions in form
     and substance satisfactory to (in their sole and absolute discretion) and
     approved by the Agent and the Majority Banks in writing; and (ii) up to
     $100,000,000 (but not to exceed, when combined with amounts of Indebtedness
     incurred pursuant to clause (i) of this [Section]9.1(k), $175,000,000) of
     Indebtedness which may rank PARI PASSU with the Obligations; PROVIDED,
     HOWEVER, that the terms of such Indebtedness shall include the following:
     (A) the maturity date of any such Indebtedness occurs at least one hundred
     twenty (120) days

<PAGE>   53

                                      -46-

     following the Revolving Credit Loan Maturity Date; (B) with respect to
     subordinated Indebtedness described in clause (i) of this [Section]9.1(k),
     no principal, interest, fees or other amounts with respect thereto are due
     and payable upon the occurrence and during the continuance of a Default or
     Event of Default; (C) with respect to subordinated Indebtedness described
     in clause (i) of this [Section]9.1(k), no principal or sinking fund
     payments are due prior to at least one hundred twenty (120) days following
     the Revolving Credit Loan Maturity Date; (D) the rate of interest and other
     fees applicable to such Indebtedness are, in the reasonable judgment of the
     Agent and the Majority Banks, a market rate for companies with the same or
     similar financial profile as the Borrower; (E) the covenants, including
     affirmative, negative and financial covenants, included therein are, in the
     reasonable judgment of the Agent and the Majority Banks, less restrictive
     than the covenants set forth in [Sections]8, 9 and 10 hereof and do
     not contain a negative pledge on assets of the Borrower and the other
     Transaction Parties (but may, with respect to PARI PASSU Indebtedness
     described in clause (ii) of this [Section]9.1(k), contain an "equal and
     ratable clause" with respect to any collateral obtained by the Agent and
     the Banks); (F) the terms and conditions of which may not be amended
     without the prior written consent of the Agent and the Majority Banks; (G)
     default provisions with respect to which do not cross-default to the Credit
     Agreement and the other Loan Documents, except that, with respect to PARI
     PASSU Indebtedness described in clause (ii) of this [Section]9.1(k), such
     default provisions may cross-default to a Default or Event of Default under
     [Section]13.1(a) or (b), to the extent that any such Default or Event of
     Default is not cured or waived within thirty (30) days after the occurrence
     thereof; and (H) such other terms and conditions as the Agent and the
     Majority Banks may reasonably require; PROVIDED, FURTHER, that prior to the
     incurrence of any such Indebtedness, the Borrower shall provide to the
     Agent PRO FORMA financial statements and compliance certificates in the
     form of EXHIBIT C indicating that for the period from the date of the
     incurrence of such Indebtedness until the Revolving Credit Loan Maturity
     Date, no Default or Event of Default would result from the incurrence of
     such Indebtedness; and

          (l) Indebtedness not otherwise set forth in clauses (a)-(k) of this
     [Section]9.1 in an amount not to exceed $2,000,000 in the aggregate.

     9.2. RESTRICTIONS ON LIENS. The Borrower will not, and will not permit any
of the other Transaction Parties to, (i) create or incur or suffer to be created
or incurred or to exist any lien, encumbrance, mortgage, pledge, charge,
restriction or other security interest of any kind upon any of its property or
assets of any character whether now owned or hereafter acquired, or upon the
income or profits therefrom; (ii) transfer any of such property or assets or the
income or profits therefrom for the purpose of subjecting the same to the
payment of Indebtedness or performance of any other obligation in priority to
payment of its general creditors; (iii) acquire, or agree or have an option to
acquire, any property or assets upon conditional sale or other title retention
or purchase money security agreement, device or arrangement; (iv) suffer to
exist

<PAGE>   54

                                      -47-

for a period of more than sixty (60) days after the same shall have been
incurred any Indebtedness or claim or demand against it that if unpaid might by
law or upon bankruptcy or insolvency, or otherwise, be given any priority
whatsoever over its general creditors; or (v) sell, assign, pledge or otherwise
transfer any accounts, contract rights, general intangibles, chattel paper or
instruments, with or without recourse; PROVIDED that the Borrower and any of the
other Transaction Parties may create or incur or suffer to be created or
incurred or to exist:

          (a) liens in favor of the Borrower on all or part of the assets of any
     of the other Transaction Parties securing Indebtedness permitted by
     [Section]9.1 and owing by such other Transaction Parties to the Borrower;

          (b) liens to secure taxes, assessments and other government charges in
     respect of obligations not overdue or liens on properties to secure claims
     for labor, material or supplies in respect of obligations not overdue;

          (c) deposits or pledges made in connection with, or to secure payment
     of, workmen's compensation, unemployment insurance, old age pensions or
     other social security obligations;

          (d) liens on properties in respect of judgments or awards, the
     Indebtedness with respect to which is permitted by [Section]9.1(d);

          (e) liens of carriers, warehousemen, mechanics and materialmen, and
     other like liens on properties in existence less than 120 days from the
     date of creation thereof in respect of obligations not overdue;

                (f) encumbrances on Real Estate consisting of easements, rights
      of way, zoning restrictions, restrictions on the use of real property and
      defects and irregularities in the title thereto, landlord's or lessor's
      liens under leases to which the Borrower or any of the other Transaction
      Parties is a party, and other minor liens or encumbrances none of which in
      the opinion of the Borrower interferes materially with the use of the
      property affected in the ordinary conduct of the business of the Borrower
      and the other Transaction Parties, which defects do not individually or in
      the aggregate have a materially adverse effect on the business of the
      Borrower individually or of the Borrower and the other Transaction Parties
      on a consolidated basis;

          (g) liens existing on the date hereof and listed on SCHEDULE 9.2
     hereto;

          (h) purchase money security interests in or purchase money mortgages
     on real or personal property acquired after the date hereof to secure
     purchase money Indebtedness of the type and amount permitted by
     [Section]9.1(g), incurred in connection with the acquisition of such
     property,

<PAGE>   55

                                      -48-

     which security interests or mortgages cover only the real or personal
     property so acquired;

          (i) liens on the Securities for so long as they constitute Margin
     Stock and on any other Margin Stock held by the Borrower or the other
     Transaction Parties; and

          (j) liens on the capital stock of Hadco Acquisition until the earlier
     to occur of the Guaranty Delivery Date or the date on which the Securities
     no longer constitute Margin Stock.

     9.3. RESTRICTIONS ON INVESTMENTS. The Borrower will not, and will not
permit any of the other Transaction Parties to, make or permit to exist or to
remain outstanding any Investment except for in Investments in:

          (a) marketable direct or guaranteed obligations of the United States
     of America that mature within one (1) year from the date of purchase by the
     Borrower;

          (b) demand deposits, certificates of deposit, bankers acceptances,
     money market deposits and time deposits of any of the Banks (including
     branches of any of the Banks) or other United States banks having total
     assets in excess of $1,000,000,000;

          (c) securities commonly known as "commercial paper" issued by a
     corporation organized and existing under the laws of the United States of
     America or any state thereof that at the time of purchase have been rated
     and the ratings for which are not less than "P 1" if rated by Moody's
     Investors Services, Inc., and not less than "A 1" if rated by Standard and
     Poor's;

          (d) mutual funds which invest solely in the types of Investments
     described in [Section]9.3(a), (b) and (c);

          (e) Investments existing on the date hereof and listed on SCHEDULE 9.3
     hereto;

          (f) Investments consisting of the Guaranties or Investments by the
     Borrower in (i) any of the Guarantors or (ii) Hadco FSC in an aggregate
     amount not to exceed $2,000,000;

          (g) Investments with respect to Indebtedness permitted by (i)
     [Section]9.1(i)(iii) and (iv) and (ii) until the occurrence of the Guaranty
     Delivery Date, [Section]9.1(i)(v);

          (h) Investments consisting of promissory notes received as proceeds of
     asset dispositions permitted by [Section]9.5.3 and Investments otherwise
     permitted by [Section]9.5.2;

<PAGE>   56

                                      -49-

          (i) Investments consisting of loans and advances to employees for
     moving, entertainment, travel and other similar expenses in the ordinary
     course of business not to exceed $2,000,000 in the aggregate at any time
     outstanding;

          (j) marketable direct or guaranteed obligations of United States
     municipalities that are rated by Standard and Poor's and Moody's Investors
     Services, Inc. as investment grade and that mature within five (5) years
     from the date of purchase by the Borrower, in an amount not to exceed
     $2,000,000 from any one issuing municipality and in an aggregate amount not
     to exceed the lesser of $5,000,000 and fifty percent (50%) of all
     Investments made by the Borrower or any of the other Transaction Parties
     under [Section]9.3(a), (b), (c), (d) and (k); and

          (k) mutual funds investing in marketable direct or guaranteed
     obligations of United States municipalities that are rated by Standard and
     Poor's and Moody's Investors Services, Inc. as investment grade and that
     mature within five (5) years from the date of purchase by the Borrower, in
     an amount not to exceed $2,000,000 from any mutual fund and in an aggregate
     amount not to exceed $5,000,000.

     9.4. DISTRIBUTIONS. The Borrower will not make any Distributions, other
than the Zycon Employee Distribution.

     9.5. MERGERS AND CONSOLIDATIONS, ACQUISITIONS AND DISPOSITION OF ASSETS.
          ------------------------------------------------------------------

          9.5.1. MERGERS AND CONSOLIDATIONS. The Borrower will not, and will not
     permit any of the other Transaction Parties to, become a party to any
     merger or consolidation, except (a) the merger or consolidation of one or
     more Subsidiaries of the Borrower with and into the Borrower, (b) the
     merger or consolidation of two or more Subsidiaries of the Borrower, (c)
     the merger or consolidation of a Target with and into the Borrower or one
     of its Subsidiaries, and (d) pursuant to the terms of the Merger Documents,
     the Merger.

          9.5.2. ACQUISITIONS. The Borrower will not, and will not permit any of
     the other Transaction Parties to agree to or effect any asset acquisition
     or stock acquisition (other than the acquisition of assets in the ordinary
     course of business consistent with past practices to the extent permitted
     by [Section]10.2); PROVIDED, HOWEVER, that (a) the Borrower may effect
     asset or stock acquisitions in an aggregate amount not to exceed
     $5,000,000; (b) the Borrower may make stock acquisitions (in addition to
     those otherwise permitted or contemplated by this [Section]9.5.2 in an
     amount not to exceed five percent (5%) of the capital stock of or other
     interest in any entity and in an aggregate amount for all such acquisitions
     not to exceed at any time ten percent (10%) of the Borrower's Consolidated
     Net Worth; PROVIDED, HOWEVER, that the writtent consent of the Majority
     Banks shall shall be required with respect to any individual such

<PAGE>   57

                                      -50-

     acquisition in an amount equal to the lesser of (i) five percent (5%) of
     the Borrower's Consolidated Net Worth at the time of such acquisition and
     (ii) $5,000,000; and (c) subject to the requirements of this
     [Section]9.5.2(c), the Borrower may effect asset or stock acquisitions
     ("Permitted Acquisitions") in addition to those otherwise permitted by this
     [Section]9.5.2 to the extent that (i) the business to be acquired (the
     "Target") is in the same or similar lines of business as the Borrower and
     the other Transaction Parties, (ii) each of the annual financial statements
     of the Target for each of the immediately preceding three (3) fiscal years
     of the Target and its Subsidiaries, if any, show a positive net income
     prior to adjustments, (iii) following the completion of such Permitted
     Acquisition, the Borrower or one of its wholly owned Subsidiaries shall own
     one hundred percent (100%) of the stock and assets of the Target and its
     Subsidiaries, if any, (iv) as of the date of such Permitted Acquisition, no
     Default or Event of Default shall have occurred and be continuing or shall
     occur after giving effect thereto and (v) contemporaneously with the
     closing of such Permitted Acquisition, the Borrower shall provide to the
     Agent and the Banks a compliance certificate in the form of EXHIBIT E-1,
     duly certified by the principal financial or accounting officer of the
     Borrower, indicating the Borrower's compliance with the financial covenants
     contained in [Section]10 immediately prior to and, on a PRO FORMA basis,
     immediately following such acquisition; and PROVIDED FURTHER that,
     contemporaneously with the closing of such acquisition, such newly acquired
     Subsidiary shall, pursuant to documentation in form and substance
     satisfactory to the Agent and the Agent's Special Counsel, become a party
     to and Guarantor under, and be bound by all of the terms and conditions of,
     a Guaranty in the form of EXHIBIT E hereto and shall provide to the Agent,
     in addition to such Guaranty, such evidence of corporate authorization,
     legal opinions and other documentation as the Agent may request. To the
     extent that any such Permitted Acquisition alters the accuracy or
     completeness of any of the Schedules hereto, the Borrower shall deliver to
     the Agent, contemporaneously with the delivery of the loan documentation
     referred to above, revised schedules reflecting changes resulting from such
     Permitted Acquisition; PROVIDED that the Agent shall only be required to
     accept such revised schedules, and such revised schedules shall only become
     part of this Credit Agreement, in the event that the Borrower shall have
     taken any and all action necessary to bring such newly acquired Subsidiary
     into compliance with each representation and warranty set forth herein,
     including in [Section]7 hereof; and PROVIDED FURTHER that no change
     resulting from any Permitted Acquisition would have a material adverse
     effect on the Borrower and the other Transaction Parties, taken as a whole.

          9.5.3. DISPOSITION OF ASSETS. The Borrower will not, and will not
     permit any of the other Transaction Parties to, become a party to or agree
     to or effect any disposition of assets, other than the disposition of
     assets in the ordinary course of business, consistent with past practices.

<PAGE>   58

                                      -51-

     9.6. SALE AND LEASEBACK. Except for arrangements described on SCHEDULE 9.6
and arrangements with respect to which the property being sold or transferred
has an aggregate fair market value not to exceed $10,000,000 for all such
arrangements, the Borrower will not, and will not permit any of the other
Transaction Parties to, enter into any arrangement, directly or indirectly,
whereby the Borrower or any of the other Transaction Parties shall sell or
transfer any property owned by it in order then or thereafter to lease such
property or lease other property that the Borrower or any of the other
Transaction Parties intends to use for substantially the same purpose as the
property being sold or transferred.

     9.7. COMPLIANCE WITH ENVIRONMENTAL LAWS. Except to the extent that any of
the following would not have a material adverse effect on the business, assets
or financial condition of the Transaction Parties, considered as a whole, the
Borrower will not, and will not permit any of the other Transaction Parties to,
(i) use any of the Real Estate or any portion thereof for the handling,
processing, storage or disposal of Hazardous Substances, (ii) cause or permit to
be located on any of the Real Estate any underground tank or other underground
storage receptacle for Hazardous Substances, (iii) generate any Hazardous
Substances on any of the Real Estate, (iv) conduct any activity at any Real
Estate or use any Real Estate in any manner so as to cause a release (i.e.
releasing, spilling, leaking, pumping, pouring, emitting, emptying, discharging,
injecting, escaping, leaching, disposing or dumping) or threatened release of
Hazardous Substances on, upon or into the Real Estate or (v) otherwise conduct
any activity at any Real Estate or use any Real Estate in any manner that would
violate any Environmental Law or bring such Real Estate in violation of any
Environmental Law.

     9.8. EMPLOYEE BENEFIT PLANS. None of the Borrower, Zycon or any ERISA
Affiliate will

          (a) engage in any "prohibited transaction" within the meaning of
     [Section]406 of ERISA or [Section]4975 of the Code which could result in a
     material liability for the Borrower or any of the other Transaction
     Parties; or

          (b) permit any Guaranteed Pension Plan to incur an "accumulated
     funding deficiency", as such term is defined in [Section]302 of ERISA,
     whether or not such deficiency is or may be waived; or

          (c) fail to contribute to any Guaranteed Pension Plan to an extent
     which, or terminate any Guaranteed Pension Plan in a manner which, could
     result in the imposition of a lien or encumbrance on the assets of the
     Borrower or any of the other Transaction Parties pursuant to
     [Section]302(f) or [Section]4068 of ERISA; or

          (d) amend any Guaranteed Pension Plan in circumstances requiring the
     posting of security pursuant to [Section]307 of ERISA or
     [Section]401(a)(29) of the Code; or

<PAGE>   59

                                      -52-

          (e) permit or take any action which would result in the aggregate
     benefit liabilities (with the meaning of [Section]4001 of ERISA) of all
     Guaranteed Pension Plans exceeding the value of the aggregate assets of
     such Plans, disregarding for this purpose the benefit liabilities and
     assets of any such Plan with assets in excess of benefit liabilities.

     9.9. CHANGES TO TRANSACTION DOCUMENTS. The Borrower will not, and will not
permit any of the other Transaction Parties to amend, supplement or waive in any
material respect the Merger Documents or the Tender Offer Documents or any term
or condition set forth in the Merger Documents or in the Tender Offer Documents
without the prior written consent of the Agent and the Majority Banks; PROVIDED,
HOWEVER, that the Borrower may file with the Securities and Exchange Commission
an amendment of such documents on Form 14d-1 upon the consummation of the Tender
Offer, which amendment does not amend any of the terms or conditions set forth
in the Merger Documents or the Tender Offer Documents but merely confirms the
consummation of the Tender Offer.

     9.10. CAPITALIZATION. The Borrower will not and will not permit any of the
other Transaction Parties to designate, establish or create any new or
additional series of capital stock or effect or permit any change in or
amendment to its charter documents (other than a change to increase the amount
of authorized common stock of such Person) or any other document or instrument
pertaining to the terms of the capital stock of such Person (except as necessary
to effect the Merger). Neither the Borrower nor any of the other Transaction
Parties will enter into or permit to exist any contractual or other obligation
to redeem, retire or repurchase any of its capital stock.

     9.11. AGREEMENTS REGARDING HADCO FSC. Neither the Borrower nor any of the
other Transaction Parties shall permit Hadco FSC (a) to engage in any   
activities other than those directly related to its purpose as a foreign sales
corporation pursuant to [Sections]921-927 of the Code or (b) at any time to
own, hold or have an interest in property or assets, whether tangible or
intangible and including cash and cash equivalents, with a fair market value in
excess of $2,000,000.

                    10. FINANCIAL COVENANTS OF THE BORROWER.
                        -----------------------------------

     The Borrower covenants and agrees that, so long as any Loan, Unpaid
Reimbursement Obligation, Letter of Credit or Note is outstanding or any Bank
has any obligation to make any Loans or the Agent has any obligation to issue,
extend or renew any Letters of Credit:

     10.1. FUNDED DEBT TO EBITDA. The Borrower will not, as at the end of any
four consecutive fiscal quarters of the Borrower, permit the ratio of (a)
Consolidated Funded Debt to (b) EBITDA to be greater than the ratio set forth
opposite such period in such table:

<PAGE>   60

                                      -53-

<TABLE>
<CAPTION>

            Period                            Ratio
            ------                            -----

  <S>                                         <C>
  Closing Date - October 31, 1997             2.75:1
  November 1, 1997 and thereafter             2.50:1

</TABLE>

<TABLE>

     10.2. CAPITAL EXPENDITURES. The Borrower will not make, or permit any of
the other Transaction Parties to make, Capital Expenditures in any fiscal year
that exceed, in the aggregate for the Borrower and the other Transaction
Parties, the amount set forth in the table below opposite such fiscal year set
forth in such table; PROVIDED, HOWEVER, that, if during any fiscal year the
amount of Capital Expenditures permitted for that fiscal year is not so
utilized, such unutilized amount may be utilized in the next succeeding fiscal
year but not in any subsequent fiscal year.

<CAPTION>

            Period                      Maximum Capital Expenditures
            ------                      ----------------------------

<S>                                             <C>
October 27, 1996 - October 25, 1997             $ 80,000,000
October 26, 1997 - October 31, 1998             $ 85,000,000
November 1, 1998 - October 30, 1999             $ 90,000,000
October 31, 1999 - October 28, 2000             $ 95,000,000
October 29, 2000 - October 27, 2001             $100,000,000
October 28, 2001 - January 8, 2002              $ 25,000,000

</TABLE>

<TABLE>

     10.3. DEBT SERVICE. The Borrower will not, as at the end of any fiscal
quarter ending during any period described in the table set forth below, permit
the ratio of (a) Earnings Before Interest and Taxes for such fiscal quarter to
(b) Consolidated Total Interest Expense for such fiscal quarter, to be less than
the ratio set forth opposite such period in such table:
<CAPTION>

            Period                         Ratio
            ------                         -----
<S>                                        <C>
Closing Date - July 31, 1997               3.0:1
August 1, 1997 and thereafter              3.5:1

</TABLE>

For purposes of this [Section]10.3, Earning Before Interest and Taxes and
Consolidated Total Interest Expense, for the fiscal period, from the Closing
Date until October 31, 1997, will be calculated by multiplying the amount of
Earnings Before Interest and Taxes or, as the case may be, Consolidated Total
Interest Expense for such period by a fraction, the numerator of which is the
number of days which have elapsed since the Closing Date and the denominator of
which is three hundred sixty-five (365).

<PAGE>   61

                                      -54-

     10.4. CONSOLIDATED NET WORTH. The Borrower will not permit Consolidated Net
Worth at any time to be less than the sum of (a) $60,000,000 PLUS (b) on a
cumulative basis, fifty percent (50%) of positive Consolidated Net Income (not
to be reduced for losses) for each fiscal quarter beginning with the fiscal
quarter ended January 31, 1997, PLUS (c) one hundred percent (100%) of the net
proceeds of any sale by the Borrower of (i) equity securities issued by the
Borrower or (ii) warrants or subscription rights for equity securities issued by
the Borrower.

                             11. CLOSING CONDITIONS.
                                 ------------------

     The obligations of the Banks to make the initial Loans and of the Agent to
issue any initial Letters of Credit shall be subject to the satisfaction of the
following conditions precedent on or prior to January 31, 1997.

     11.1. LOAN DOCUMENTS; TRANSACTION DOCUMENTS.
           -------------------------------------

          11.1.1. LOAN DOCUMENTS. Each of the Loan Documents shall have been
     duly executed and delivered by the respective parties thereto, shall be in
     full force and effect and shall be in form and substance satisfactory to
     each of the Banks. Each Bank shall have received a fully executed copy of
     each such document.

          11.1.2. TRANSACTION DOCUMENTS. Each of the other Transaction Documents
     shall have been duly executed and delivered by the respective parties
     thereto, shall be in full force and effect and shall be in form and
     substance satisfactory to each of the Banks. Each Bank shall have received
     a fully executed copy of each such document.

     11.2. CERTIFIED COPIES OF CHARTER DOCUMENTS. Each of the Banks shall have
received from the Borrower and Hadco Acquisition, Zycon, Zycon Alternate
Circuits, Inc. and Zycon Corp. SDN BHD a copy, certified by a duly authorized
officer of such Person to be true and complete on the Closing Date, of each of
(i) its charter or other incorporation documents as in effect on such date of
certification, and (ii) its by-laws as in effect on such date.

     11.3. CORPORATE ACTION. All corporate action necessary for the valid
execution, delivery and performance by the Borrower and each of the other
Transaction Parties of this Credit Agreement and the other Transaction Documents
to which it is or is to become a party shall have been duly and effectively
taken, and evidence thereof satisfactory to the Banks shall have been provided
to each of the Banks.

     11.4. INCUMBENCY CERTIFICATE. Each of the Banks shall have received from an
incumbency certificate, dated as of the Closing Date, signed by a duly
authorized officer of such Transaction Party, and giving the name and bearing a
specimen signature of each individual who shall be authorized: (i) to sign, in
the name and on behalf of each such Transaction Party, each of the Transaction
Documents to which such Transaction Party is or is to become a party; (ii) in
the

<PAGE>   62

                                      -55-

case of the Borrower, to make Loan Requests and Conversion Requests and to apply
for Letters of Credit; and (iii) to give notices and to take other action on its
behalf under the Transaction Documents to which it is a party.

     11.5. VALIDITY OF LIENS; UCC SEARCH RESULTS.
           -------------------------------------

          11.5.1. VALIDITY OF LIENS. The Stock Pledge Agreement shall be
     effective to create in favor of the Agent a legal, valid and enforceable
     first (except for Permitted Liens entitled to priority under applicable
     law) security interest in and lien upon the Securities.

          11.5.2. UCC SEARCH RESULTS. The Agent shall have received from each of
     the Borrower and the other Transaction Parties the results of UCC searches
     in jurisdictions certified by the Borrower as constituting the locations of
     all offices and locations, including the chief executive office, of the
     Borrower and each of the other Transaction Parties and in such other
     jurisdictions as the Agent may request, indicating no liens other than
     Permitted Liens and otherwise in form and substance satisfactory to the
     Agent.

     11.6. CERTIFICATES OF INSURANCE. The Agent shall have received (i) a
certificate of insurance from an independent insurance broker dated as of the
Closing Date, identifying insurers, types of insurance, insurance limits, and
policy terms, and otherwise describing the insurance obtained in accordance with
the provisions of this Credit Agreement and (ii) certified copies of all
policies evidencing such insurance (or certificates therefore signed by the
insurer or an agent authorized to bind the insurer).

     11.7. FORM U-1. Each of the Borrower and Hadco Acquisition shall have
provided to the Agent and each of the Banks a duly completed and executed Form
U-1, as specified by Regulation U of the Federal Reserve Board of Governors.

     11.8. SOLVENCY CERTIFICATE. Each of the Banks shall have received an
officer's certificate of the Borrower dated as of the Closing Date as to the
solvency of the Borrower and the other Transaction Parties following the
consummation of the transactions contemplated herein and in the other
Transaction Documents and in form and substance satisfactory to the Banks.

     11.9. OPINION OF COUNSEL. Each of the Banks and the Agent shall have
received a favorable legal opinion addressed to the Banks and the Agent, dated
as of the Closing Date, in form and substance satisfactory to the Banks and the
Agent, from Berlin, Hamilton & Dahmen, counsel to the Borrower and its
Subsidiaries.

     11.10. PAYMENT OF FEES. The Borrower shall have paid to the Banks or the
Agent, as appropriate, any Letter of Credit fees and the fees payable pursuant
to [Section]5.1 and the Agent's Side Letter.

<PAGE>   63

                                      -56-

     11.11. TENDER OFFER.
            ------------

          11.11.1. ADEQUATE TENDER OF SECURITIES. Hadco Acquisition or the
     Borrower shall have received, as of the Closing Date, proper tenders of
     Securities which shall represent at least a majority of the Securities, and
     as to which Securities all (if any) rights of withdrawal of the tendering
     shareholders under Section 14(d)(5) of the Securities Exchange Act of 1934,
     as amended, and the regulations thereunder with respect to such Securities
     shall have expired or will expire upon the purchase thereof.

          11.11.2. CONSUMMATION OF TENDER OFFER. All of the conditions to the
     purchase of the Securities pursuant to the Tender Offer Documents shall
     have been satisfied, and none of such conditions shall have been amended,
     supplemented or waived except with the consent of the Agent and the
     Majority Banks.

     11.12. UNUSED DEBT CAPACITY. Immediately following the closing and
consummation of the Tender Offer, the amount by which the Total Commitment
exceeds the sum of the Loans outstanding (after giving effect to all amounts
requested) PLUS the Maximum Drawing Amount plus any Unpaid Reimbursement
Obligations shall be at least $25,000,000.

     11.13. PAYMENT OF EXISTING INDEBTEDNESS; CONSENT OF OTHER LENDERS.
            ----------------------------------------------------------

          11.13.1. INDEBTEDNESS OF THE BORROWER TO FNBB. The Borrower shall have
     repaid all obligations to FNBB under the Revolving Credit Agreement dated
     as of July 10, 1996 between the Borrower and FNBB, including principal,
     interest, fees and other amounts owing thereunder, and FNBB shall have
     returned to the Borrower the Note (as defined in such Revolving Credit
     Agreement dated as of July 10, 1996), marked "Cancelled".

          11.13.2. INDEBTEDNESS OF ZYCON TO COMERICA BANK - CALIFORNIA. The 
     Agent shall have received a payoff letter, satisfactory in form and 
     substance to the Agent, from Comerica Bank - California, indicating all 
     loan obligations of Zycon and its Subsidiaries to Comerica Bank - 
     California to be discharged on the Closing Date and an agreement by 
     Comerica Bank - California that upon receipt of such funds, all such loan 
     obligations shall be paid in full and it will forthwith execute and 
     deliver to the Agent for filing all termination statements and take such 
     other actions as may be necessary to discharge all mortgages, deeds of 
     trust and security interests granted by Zycon or any of its Subsidiaries 
     in favor of Comerica Bank - California.

          11.13.3. CONSENT OF EQUIPMENT LESSORS. The Agent shall have received
     evidence of the consent, in form and substance satisfactory to the Agent,
     of each of CIT Group/Equipment Financing, Inc.,

<PAGE>   64

                                      -57-

     MetLife Capital Corporation and Heller Financial, Inc. to the purchase by
     Hadco Acquisition of the Securities, to the Merger and to the other
     transactions contemplated hereby and by the other Transaction Documents.

          11.13.4. NEW YORK URBAN DEVELOPMENT CORPORATION. The Agent shall have
     received evidence of the consent, in form and substance satisfactory to the
     Agent, of New York Urban Development Corporation to the purchase by Hadco
     Acquisition of the Securities, the loan by the Borrower to Hadco
     Acquisition of sufficient proceeds of the Loans to enable the purchase of
     the Securities and to the other transactions contemplated hereby and by the
     other Transaction Documents.

          11.13.5. NOTICE TO BANK BUMIPUTRA. The Borrower or Zycon shall have
     complied with all notice and other requirements set forth in the Bank
     Bumiputra Loan Agreement resulting from the transactions contemplated by
     the Transaction Documents.

     11.14. POST-CLOSING UNDERTAKINGS. The conditions, actions and items set
forth on SCHEDULE 8.18 shall not be deemed waived by virtue of the fact that
they are not completed on the Closing Date.

                        12. CONDITIONS TO ALL BORROWINGS.
                            ----------------------------

     The obligations of the Banks to make any Loan, and of the Agent to issue,
extend or renew any Letter of Credit, in each case whether on or after the
Closing Date, shall also be subject to the satisfaction of the following
conditions precedent:

     12.1. REPRESENTATIONS TRUE; NO EVENT OF DEFAULT. Each of the
representations and warranties of any of the Borrower and the Guarantors
contained in this Credit Agreement, the other Transaction Documents or in any
document or instrument delivered pursuant to or in connection with this Credit
Agreement shall be true as of the date as of which they were made and shall also
be true at and as of the time of the making of such Loan or the issuance,
extension or renewal of such Letter of Credit, with the same effect as if made
at and as of that time (except to the extent of changes resulting from
transactions contemplated or permitted by this Credit Agreement and the other
Loan Documents and changes occurring in the ordinary course of business that
singly or in the aggregate are not materially adverse, and to the extent that
such representations and warranties relate expressly to an earlier date) and no
Default or Event of Default shall have occurred and be continuing. The Agent
shall have received a certificate of the Borrower signed by an authorized
officer of the Borrower to such effect.

     12.2. NO LEGAL IMPEDIMENT. No change shall have occurred in any law or
regulations thereunder or interpretations thereof that in the reasonable opinion
of any Bank would make it illegal for such Bank to make such Loan or to
participate in the issuance, extension or renewal of such Letter of Credit or in

<PAGE>   65

                                      -58-

the reasonable opinion of the Agent would make it illegal for the Agent to
issue, extend or renew such Letter of Credit.

     12.3. GOVERNMENTAL REGULATION. Each Bank shall have received such
statements in substance and form reasonably satisfactory to such Bank as such
Bank shall require for the purpose of compliance with any applicable regulations
of the Comptroller of the Currency or the Board of Governors of the Federal
Reserve System.

     12.4. PROCEEDINGS AND DOCUMENTS. All proceedings in connection with the
transactions contemplated by this Credit Agreement, the other Transaction
Documents and all other documents incident thereto shall be satisfactory in
substance and in form to the Banks and to the Agent and the Agent's Special
Counsel, and the Banks, the Agent and such counsel shall have received all
information and such counterpart originals or certified or other copies of such
documents as the Agent may reasonably request.

                    13. EVENTS OF DEFAULT; ACCELERATION; ETC.
                        ------------------------------------

     13.1. EVENTS OF DEFAULT AND ACCELERATION. If any of the following events
("Events of Default" or, if the giving of notice or the lapse of time or both is
required, then, prior to such notice or lapse of time, "Defaults") shall occur:

          (a) the Borrower shall fail to pay any principal of the Loans or any
     Reimbursement Obligation when the same shall become due and payable,
     whether at the stated date of maturity or any accelerated date of maturity
     or at any other date fixed for payment;

          (b) the Borrower or any of the other Transaction Parties shall fail to
     pay any interest on the Loans, the commitment fee, any Letter of Credit
     Fee, the Agent's fee, or other sums due hereunder or under any of the other
     Loan Documents, within two (2) Business Days after the day on which the
     same shall become due and payable, whether at the stated date of maturity
     or any accelerated date of maturity or at any other date fixed for payment;

          (c) the Borrower shall fail to comply with any of its covenants
     contained in [Section]8, 9 or 10;

          (d) the Borrower or any of the other Transaction Parties shall fail to
     perform any term, covenant or agreement contained herein or in any of the
     other Loan Documents (other than those specified elsewhere in this
     [Section]13.1) for twenty (20) days after written notice of such failure
     has been given to the Borrower by the Agent;

          (e) any representation or warranty of the Borrower or any of the other
     Transaction Parties in this Credit Agreement or any of the other
     Transaction Documents or in any other document or instrument delivered
     pursuant to or in connection with this Credit Agreement shall prove to

<PAGE>   66

                                      -59-

     have been false in any material respect upon the date when made or deemed
     to have been made or repeated;

          (f) the Borrower or any of the other Transaction Parties shall fail to
     pay at maturity, or within any applicable period of grace, any obligations
     for borrowed money or credit received or in respect of any Capitalized
     Leases, which obligations exceed $5,000,000 in the aggregate, or fail to
     observe or perform any material term, covenant or agreement contained in
     any agreement by which it is bound, evidencing or securing borrowed money
     or credit received or in respect of any Capitalized Leases exceeding
     $5,000,000 in the aggregate, for such period of time as would permit
     (assuming the giving of appropriate notice if required) the holder or
     holders thereof or of any obligations issued thereunder to accelerate the
     maturity thereof;

          (g) the Borrower or any of the other Transaction Parties shall make an
     assignment for the benefit of creditors, or admit in writing its inability
     to pay or generally fail to pay its debts as they mature or become due, or
     shall petition or apply for the appointment of a trustee or other
     custodian, liquidator or receiver of the Borrower or any of the other
     Transaction Parties or of any substantial part of the assets of the
     Borrower or any of the other Transaction Parties or shall commence any case
     or other proceeding relating to the Borrower or any of the other
     Transaction Parties under any bankruptcy, reorganization, arrangement,
     insolvency, readjustment of debt, dissolution or liquidation or similar law
     of any jurisdiction, now or hereafter in effect, or shall take any action
     to authorize or in furtherance of any of the foregoing, or if any such
     petition or application shall be filed or any such case or other proceeding
     shall be commenced against the Borrower or any of the other Transaction
     Parties and the Borrower or any of the other Transaction Parties shall
     indicate its approval thereof, consent thereto or acquiescence therein or
     such petition or application shall not have been dismissed within
     forty-five (45) days following the filing thereof;

          (h) a decree or order is entered appointing any such trustee,
     custodian, liquidator or receiver or adjudicating the Borrower or any of
     the other Transaction Parties bankrupt or insolvent, or approving a
     petition in any such case or other proceeding, or a decree or order for
     relief is entered in respect of the Borrower or any of the other
     Transaction Parties in an involuntary case under federal bankruptcy laws as
     now or hereafter constituted;

          (i) there shall remain in force, undischarged, unsatisfied and
     unstayed, for more than thirty (30) days, any final judgment against the
     Borrower or any of the other Transaction Parties that, with other
     outstanding final judgments, undischarged, against the Borrower or any of
     the other Transaction Parties exceeds in the aggregate $5,000,000;

<PAGE>   67

                                      -60-

          (j) if any of the Transaction Documents shall be cancelled,
     terminated, revoked or rescinded, or the Agent's security interest in a
     substantial portion of the Securities shall cease to be perfected, or shall
     cease to have the priority contemplated by the Stock Pledge Agreement, in
     each case otherwise than in accordance with the terms thereof or with the
     express prior written agreement, consent or approval of the Banks, or any
     action at law, suit or in equity or other legal proceeding to cancel,
     revoke or rescind any of the Transaction Documents shall be commenced by or
     on behalf of the Borrower or any of the other Transaction Parties party
     thereto or any of their respective stockholders, or any court or any other
     governmental or regulatory authority or agency of competent jurisdiction
     shall make a determination that, or issue a judgment, order, decree or
     ruling to the effect that, any one or more of the Transaction Documents is
     illegal, invalid or unenforceable in accordance with the terms thereof;

          (k) the Borrower, Zycon or any ERISA Affiliate incurs any liability to
     the PBGC or a Guaranteed Pension Plan pursuant to Title IV of ERISA in an
     aggregate amount exceeding $2,000,000; the Borrower, Zycon or any ERISA
     Affiliate is assessed withdrawal liability pursuant to Title IV of ERISA by
     a Multiemployer Plan requiring aggregate annual payments exceeding
     $2,000,000, or any of the following occurs with respect to a Guaranteed
     Pension Plan: (i) an ERISA Reportable Event, or a failure to make a
     required installment or other payment (within the meaning of
     [Section]302(f)(1) of ERISA), provided the Agent determines in its
     reasonable discretion that such event (A) could be expected to result in
     liability of the Borrower or Zycon to the PBGC or the Plan in an aggregate
     amount exceeding $2,000,000 and (B) could constitute grounds for the
     termination of such Plan by the PBGC, for the appointment by the
     appropriate United States District Court of a trustee to administer such
     Plan or for the imposition of a lien in favor of the Guaranteed Pension
     Plan; (ii) the appointment by a United States District court of a trustee
     to administer such Plan; or (iii) the institution by the PBGC of
     proceedings to terminate such Plan;

          (l) the Borrower or any of the other Transaction Parties shall be
     enjoined, restrained or in any way prevented by the order of any court or
     any administrative or regulatory agency from conducting any material part
     of its business and such order shall continue in effect for more than
     thirty (30) days;

          (m) there shall occur any strike, lockout, labor dispute, embargo,
     condemnation, act of God or public enemy, or other casualty, which in any
     such case causes, for more than fifteen (15) consecutive days, the
     cessation or substantial curtailment of revenue producing activities at any
     facility of the Borrower or any of the other Transaction Parties if such
     event or circumstance is not covered by business interruption insurance and
     would have a material adverse effect on the business or financial

<PAGE>   68

                                      -61-

     condition of the Borrower and the other Transaction Parties, considered as
     a whole;

          (n) there shall occur the loss, suspension or revocation of, or
     failure to renew, any license or permit now held or hereafter acquired by
     the Borrower or any of the other Transaction Parties if such loss,
     suspension, revocation or failure to renew would have a material adverse
     effect on the business or financial condition of the Borrower and the other
     Transaction Parties, considered as a whole;

          (o) the Borrower or any of the other Transaction Parties shall be
     indicted for a state or federal crime, or any civil or criminal action
     shall otherwise have been brought or threatened against the Borrower or any
     the other Transaction Parties, a punishment for which in any such case
     could include the forfeiture of any assets of the Borrower or such other
     Transaction Party having a fair market value in excess of $1,000,000; or

          (p) any person or group of persons (within the meaning of Section 13
     or 14 of the Securities Exchange Act of 1934, as amended) shall have
     acquired beneficial ownership (within the meaning of Rule 13d-3 promulgated
     by the Securities and Exchange Commission under said Act) of thirty percent
     (30%) or more of the outstanding shares of common stock of the Borrower;
     or, during any period of twelve consecutive calendar months, individuals
     who were directors of the Borrower on the first day of such period shall
     cease to constitute a majority of the board of directors of the Borrower or
     the Borrower shall, at any time, legally or beneficially own less than
     ninety percent (90%) of the shares of the capital stock of Hadco
     Acquisition (on a fully diluted basis), whether before or after the
     consummation of the Merger;

then, and in any such event, so long as the same may be continuing, the Agent
may, and upon the request of the Majority Banks shall, by notice in writing to
the Borrower declare all amounts owing with respect to this Credit Agreement,
the Notes and the other Loan Documents and all Reimbursement Obligations to be,
and they shall thereupon forthwith become, immediately due and payable without
presentment, demand, protest or other notice of any kind, all of which are
hereby expressly waived by the Borrower; PROVIDED that in the event of any Event
of Default specified in [Sections]13.1(g) or 13.1(h), all such amounts shall
become immediately due and payable automatically and without any requirement of
notice from the Agent or any Bank.

     13.2. TERMINATION OF COMMITMENTS. If any one or more of the Events of
Default specified in [Section]13.1(g) or [Section]13.1(h) shall occur and be
continuing, any unused portion of the credit hereunder shall forthwith terminate
and each of the Banks shall be relieved of all further obligations to make Loans
to the Borrower and the Agent shall be relieved of all further obligations to
issue, extend or renew Letters of Credit. If any other Event of Default shall
have occurred and be continuing, the Agent may and, upon the request of the
Majority Banks, shall, by notice to the Borrower, terminate the unused portion
of the credit
<PAGE>   69
                                      -62-

hereunder, and upon such notice being given such unused portion of the credit
hereunder shall terminate immediately and each of the Banks shall be relieved of
all further obligations to make Loans and the Agent shall be relieved of all
further obligations to issue, extend or renew Letters of Credit. No termination
of the credit hereunder shall relieve the Borrower or any of the other
Transaction Parties of any of the Obligations.


     13.3. REMEDIES. In case any one or more of the Events of Default shall have
occurred and be continuing, and whether or not the Banks shall have accelerated
the maturity of the Loans pursuant to [Section]13.1, each Bank, if owed any
amount with respect to the Loans or the Reimbursement Obligations, may, with the
consent of the Majority Banks but not otherwise, proceed to protect and enforce
its rights by suit in equity, action at law or other appropriate proceeding,
whether for the specific performance of any covenant or agreement contained in
this Credit Agreement and the other Loan Documents or any instrument pursuant to
which the Obligations to such Bank are evidenced, including as permitted by
applicable law the obtaining of the EX PARTE appointment of a receiver, and, if
such amount shall have become due, by declaration or otherwise, proceed to
enforce the payment thereof or any other legal or equitable right of such Bank.
No remedy herein conferred upon any Bank or the Agent or the holder of any Note
or purchaser of any Letter of Credit Participation is intended to be exclusive
of any other remedy and each and every remedy shall be cumulative and shall be
in addition to every other remedy given hereunder or now or hereafter existing
at law or in equity or by statute or any other provision of law.

                                   14. SETOFF.
                                       ------

     Regardless of the adequacy of any collateral, during the continuance of any
Event of Default, any deposits or other sums credited by or due from any of the
Banks to the Borrower and any securities or other property of the Borrower in
the possession of such Bank may be applied to or set off by such Bank against
the payment of Obligations and any and all other liabilities, direct, or
indirect, absolute or contingent, due or to become due, now existing or
hereafter arising, of the Borrower to such Bank. Each of the Banks agrees with
each other Bank that (i) if an amount to be set off is to be applied to
Indebtedness of the Borrower to such Bank, other than Indebtedness evidenced by
the Notes held by such Bank or constituting Reimbursement Obligations owed to
such Bank, such amount shall be applied ratably to such other Indebtedness and
to the Indebtedness evidenced by all such Notes held by such Bank or
constituting Reimbursement Obligations owed to such Bank, and (ii) if such Bank
shall receive from the Borrower, whether by voluntary payment, exercise of the
right of setoff, counterclaim, cross action, enforcement of the claim evidenced
by the Notes held by, or constituting Reimbursement Obligations owed to, such
Bank by proceedings against the Borrower at law or in equity or by proof thereof
in bankruptcy, reorganization, liquidation, receivership or similar proceedings,
or otherwise, and shall retain and apply to the payment of the Note or Notes
held by, or Reimbursement Obligations owed to, such Bank any amount in excess of
its ratable portion of the payments received by all of the Banks with respect to

<PAGE>   70


                                      -63-


the Notes held by, and Reimbursement Obligations owed to, all of the Banks, such
Bank will make such disposition and arrangements with the other Banks with
respect to such excess, either by way of distribution, PRO TANTO assignment of
claims, subrogation or otherwise as shall result in each Bank receiving in
respect of the Notes held by it or Reimbursement obligations owed it, its
proportionate payment as contemplated by this Credit Agreement; PROVIDED that if
all or any part of such excess payment is thereafter recovered from such Bank,
such disposition and arrangements shall be rescinded and the amount restored to
the extent of such recovery, but without interest.

                                 15. THE AGENT.
                                     ---------

     15.1. AUTHORIZATION.
           -------------

          (a) The Agent is authorized to take such action on behalf of each of
     the Banks and to exercise all such powers as are hereunder and under any of
     the other Loan Documents and any related documents delegated to the Agent,
     together with such powers as are reasonably incident thereto, PROVIDED that
     no duties or responsibilities not expressly assumed herein or therein shall
     be implied to have been assumed by the Agent.

          (b) The relationship between the Agent and each of the Banks is that
     of an independent contractor. The use of the term "Agent" is for
     convenience only and is used to describe, as a form of convention, the
     independent contractual relationship between the Agent and each of the
     Banks. Nothing contained in this Credit Agreement nor the other Loan
     Documents shall be construed to create an agency, trust or other fiduciary
     relationship between the Agent and any of the Banks.

          (c) As an independent contractor empowered by the Banks to exercise
     certain rights and perform certain duties and responsibilities hereunder
     and under the other Loan Documents, the Agent is nevertheless a
     "representative" of the Banks, as that term is defined in Article 1 of the
     Uniform Commercial Code, for purposes of actions for the benefit of the
     Banks and the Agent with respect to all collateral security and guaranties
     contemplated by the Loan Documents.


     15.2. EMPLOYEES AND AGENTS. The Agent may exercise its powers and execute
its duties by or through employees or agents and shall be entitled to take, and
to rely on, advice of counsel concerning all matters pertaining to its rights
and duties under this Credit Agreement and the other Loan Documents. The Agent
may utilize the services of such Persons as the Agent in its sole discretion may
reasonably determine, and all reasonable fees and expenses of any such Persons
shall be paid by the Borrower.


     15.3. NO LIABILITY. Neither the Agent nor any of its shareholders,
directors, officers or employees nor any other Person assisting them in their
duties nor any agent or employee thereof, shall be liable for any waiver,
consent or approval given or any action taken, or omitted to be taken, in good
faith by it 

<PAGE>   71


                                      -64-


or them hereunder or under any of the other Loan Documents, or in connection
herewith or therewith, or be responsible for the consequences of any oversight
or error of judgment whatsoever, except that the Agent or such other Person, as
the case may be, may be liable for losses due to its willful misconduct or gross
negligence.

     15.4. NO REPRESENTATIONS. The Agent shall not be responsible for the
execution or validity or enforceability of this Credit Agreement, the Notes, the
Letters of Credit, any of the other Loan Documents or any instrument at any time
constituting, or intended to constitute, collateral security for the Notes, or
for the value of any such collateral security or for the validity,
enforceability or collectability of any such amounts owing with respect to the
Notes, or for any recitals or statements, warranties or representations made
herein or in any of the other Loan Documents or in any certificate or instrument
hereafter furnished to it by or on behalf of the Borrower or any of the other
Transaction Parties, or be bound to ascertain or inquire as to the performance
or observance of any of the terms, conditions, covenants or agreements herein or
in any instrument at any time constituting, or intended to constitute,
collateral security for the Notes or to inspect any of the properties, books or
records of the Borrower or any of the Transaction Parties. The Agent shall not
be bound to ascertain whether any notice, consent, waiver or request delivered
to it by the Borrower or any holder of any of the Notes shall have been duly
authorized or is true, accurate and complete. The Agent has not made nor does it
now make any representations or warranties, express or implied, nor does it
assume any liability to the Banks, with respect to the credit worthiness or
financial conditions of the Borrower or any of the Transaction Parties. Each
Bank acknowledges that it has, independently and without reliance upon the Agent
or any other Bank, and based upon such information and documents as it has
deemed appropriate, made its own credit analysis and decision to enter into this
Credit Agreement.

     15.5. PAYMENTS.
           --------

           15.5.1. PAYMENTS TO AGENT. A payment by the Borrower to the Agent
     hereunder or any of the other Loan Documents for the account of any Bank
     shall constitute a payment to such Bank. The Agent agrees promptly to
     distribute to each Bank such Bank's PRO RATA share of payments received by
     the Agent for the account of the Banks except as otherwise expressly
     provided herein or in any of the other Loan Documents.

           15.5.2. DISTRIBUTION BY AGENT. If in the opinion of the Agent the
     distribution of any amount received by it in such capacity hereunder, under
     the Notes or under any of the other Loan Documents might involve it in
     liability, it may refrain from making distribution until its right to make
     distribution shall have been adjudicated by a court of competent
     jurisdiction. If a court of competent jurisdiction shall adjudge that any
     amount received and distributed by the Agent is to be repaid, each Person
     to whom any such distribution shall have been made shall either repay to

<PAGE>   72


                                      -65-


     the Agent its proportionate share of the amount so adjudged to be repaid or
     shall pay over the same in such manner and to such Persons as shall be
     determined by such court.


          15.5.3. DELINQUENT BANKS. Notwithstanding anything to the contrary
     contained in this Credit Agreement or any of the other Loan Documents, any
     Bank that fails (i) to make available to the Agent its pro rata share of
     any Loan or to purchase any Letter of Credit Participation or (ii) to
     comply with the provisions of [Section]14 with respect to making
     dispositions and arrangements with the other Banks, where such Bank's share
     of any payment received, whether by setoff or otherwise, is in excess of
     its PRO RATA share of such payments due and payable to all of the Banks, in
     each case as, when and to the full extent required by the provisions of
     this Credit Agreement, shall be deemed delinquent (a "Delinquent Bank") and
     shall be deemed a Delinquent Bank until such time as such delinquency is
     satisfied. A Delinquent Bank shall be deemed to have assigned any and all
     payments due to it from the Borrower, whether on account of outstanding
     Loans, Unpaid Reimbursement Obligations, interest, fees or otherwise, to
     the remaining nondelinquent Banks for application to, and reduction of,
     their respective PRO RATA shares of all outstanding Loans and Unpaid
     Reimbursement Obligations. The Delinquent Bank hereby authorizes the Agent
     to distribute such payments to the nondelinquent Banks in proportion to
     their respective pro rata shares of all outstanding Loans and Unpaid
     Reimbursement Obligations. A Delinquent Bank shall be deemed to have
     satisfied in full a delinquency when and if, as a result of application of
     the assigned payments to all outstanding Loans and Unpaid Reimbursement
     Obligations of the nondelinquent Banks, the Banks' respective PRO RATA
     shares of all outstanding Loans and Unpaid Reimbursement Obligations have
     returned to those in effect immediately prior to such delinquency and
     without giving effect to the nonpayment causing such delinquency.


     15.6. HOLDERS OF NOTES. The Agent may deem and treat the payee of any Note
or the purchaser of any Letter of Credit Participation as the absolute owner or
purchaser thereof for all purposes hereof until it shall have been furnished in
writing with a different name by such payee or by a subsequent holder, assignee
or transferee.


     15.7. INDEMNITY. The Banks ratably agree hereby to indemnify and hold
harmless the Agent from and against any and all claims, actions and suits
(whether groundless or otherwise), losses, damages, costs, expenses (including
any expenses for which the Agent has not been reimbursed by the Borrower as
required by [Section]16), and liabilities of every nature and character arising
out of or related to this Credit Agreement, the Notes, or any of the other Loan
Documents or the transactions contemplated or evidenced hereby or thereby, or
the Agent's actions taken hereunder or thereunder, except to the extent that any
of the same shall be directly caused by the Agent's willful misconduct or gross
negligence.

<PAGE>   73

                                      -66-


     15.8. AGENT AS BANK. In its individual capacity, FNBB shall have the same
obligations and the same rights, powers and privileges in respect to its
Commitment and the Loans made by it, and as the holder of any of the Notes and
as the purchaser of any Letter of Credit Participations, as it would have were
it not also the Agent.


     15.9. RESIGNATION. The Agent may resign at any time by giving sixty (60)
days prior written notice thereof to the Banks and the Borrower. Upon any such
resignation, the Majority Banks shall have the right to appoint a successor
Agent. Unless a Default or Event of Default shall have occurred and be
continuing, such successor Agent shall be reasonably acceptable to the Borrower.
If no successor Agent shall have been so appointed by the Majority Banks and
shall have accepted such appointment within thirty (30) days after the retiring
Agent's giving of notice of resignation, then the retiring Agent may, on behalf
of the Banks, appoint a successor Agent, which shall be a financial institution
having a rating of not less than A or its equivalent by Standard & Poor's
Corporation. Upon the appointment of and acceptance by a successor Agent and so
long as no Default or Event of Default has occurred and is continuing, the
resigning Agent will pay to the successor Agent a PRO RATA portion of the annual
Agent's fee described in the Agent's Side Letter, calculated by multiplying the
annual amount of such fee by a fraction, the numerator of which is 365 MINUS the
number of days which have elapsed since the Borrower's most recent payment of
such fee and the denominator of which is 365. Upon the acceptance of any
appointment as Agent hereunder by a successor Agent, such successor Agent shall
thereupon succeed to and become vested with all the rights, powers, privileges
and duties of the retiring Agent, and the retiring Agent shall be discharged
from its duties and obligations hereunder. After any retiring Agent's
resignation, the provisions of this Credit Agreement and the other Loan
Documents shall continue in effect for its benefit in respect of any actions
taken or omitted to be taken by it while it was acting as Agent.

                                  16. EXPENSES.
                                      --------

     The Borrower agrees to pay (a) the reasonable costs of producing and
reproducing this Credit Agreement, the other Loan Documents and the other
agreements and instruments mentioned herein, (b) any taxes (including any
interest and penalties in respect thereto) payable by the Agent or any of the
Banks (other than taxes based upon the Agent's or any Bank's net income) on or
with respect to the transactions contemplated by this Credit Agreement (the
Borrower hereby agreeing to indemnify the Agent and each Bank with respect
thereto), (c) the reasonable fees, expenses and disbursements of the Agent's
Special Counsel or any local counsel to the Agent incurred in connection with
the preparation, administration or interpretation of the Loan Documents and
other instruments mentioned herein, each closing hereunder, and amendments,
modifications, approvals, consents or waivers hereto or hereunder, (d) the
reasonable fees, expenses and disbursements of the Agent incurred by the Agent
in connection with the evaluation of the Borrower and the other Transaction
Parties and with the preparation, administration or interpretation of the Loan
Documents and other instruments mentioned herein, including, without 

<PAGE>   74

                                      -67-


limitation, commercial finance examination expenses, (e) all reasonable
out-of-pocket expenses (including without limitation reasonable attorneys' fees
and costs, which attorneys may be employees of any Bank or the Agent, and
reasonable consulting, accounting, appraisal, investment banking and similar
professional fees and charges) incurred by any Bank or the Agent in connection
with (i) the enforcement of or preservation of rights under any of the Loan
Documents against the Borrower or any of the other Transaction Parties or the
administration thereof after the occurrence of a Default or Event of Default and
(ii) any litigation, proceeding or dispute whether arising hereunder or
otherwise, in any way related to any Bank's or the Agent's relationship with the
Borrower or any of the other Transaction Parties (but excluding disputes solely
between or among the Banks), or related to the Merger or the Tender Offer, and
(f) all reasonable fees, expenses and disbursements of any Bank or the Agent
incurred in connection with UCC searches. The covenants of this [Section]16
shall survive payment or satisfaction of all other Obligations.

                              17. INDEMNIFICATION.
                                  ---------------

     The Borrower agrees to indemnify and hold harmless the Agent and the Banks
from and against any and all claims, actions and suits whether groundless or
otherwise, and from and against any and all liabilities, losses, damages and
expenses of every nature and character arising out of this Credit Agreement or
any of the other Loan Documents or the transactions contemplated hereby
including, without limitation, (a) any actual or proposed use by the Borrower or
any of the other Transaction Parties of the proceeds of any of the Loans or
Letters of Credit, (b) the Borrower or any of the other Transaction Parties
entering into or performing this Credit Agreement or any of the other
Transaction Documents or (c) with respect to the Borrower and the other
Transaction Parties and their respective properties and assets, the violation of
any Environmental Law, the presence, disposal, escape, seepage, leakage,
spillage, discharge, emission, release or threatened release of any Hazardous
Substances or any action, suit, proceeding or investigation brought or
threatened with respect to any Hazardous Substances (including, but not limited
to, claims with respect to wrongful death, personal injury or damage to
property), in each case including, without limitation, the reasonable fees and
disbursements of counsel and allocated costs of internal counsel incurred in
connection with any such investigation, litigation or other proceeding;
PROVIDED, HOWEVER, that such indemnity shall not apply to the portion, if any,
of any such losses, claims, damages, liabilities or related expenses of any
Person seeking indemnification that is determined by a court of competent
jurisdiction by final and nonappealable judgment to have resulted from the
willful misconduct or gross negligence of such Person seeking indemnification.
In litigation, or the preparation therefor, the Banks and the Agent shall be
entitled to select their own counsel and, in addition to the foregoing
indemnity, the Borrower agrees to pay promptly the reasonable fees and expenses
of such counsel. If, and to the extent that the obligations of the Borrower
under this [Section]17 are unenforceable for any reason, the Borrower hereby
agrees to make the maximum contribution to the payment in satisfaction of such
obligations which is permissible under

<PAGE>   75


                                      -68-


applicable law. The covenants contained in this [Section]17 shall survive
payment or satisfaction in full of all other Obligations.

                         18. SURVIVAL OF COVENANTS, ETC.
                             --------------------------

     All covenants, agreements, representations and warranties made herein, in
the Notes, in any of the other Transaction Documents or in any documents or
other papers delivered by or on behalf of the Borrower or any of the other
Transaction Parties pursuant hereto shall be deemed to have been relied upon by
the Banks and the Agent, notwithstanding any investigation heretofore or
hereafter made by any of them, and shall survive the making by the Banks of any
of the Loans and the issuance, extension or renewal of any Letters of Credit, as
herein contemplated, and shall continue in full force and effect so long as any
Letter of Credit or any amount due under this Credit Agreement or the Notes or
any of the other Loan Documents remains outstanding or any Bank has any
obligation to make any Loans or the Agent has any obligation to issue, extend or
renew any Letter of Credit, and for such further time as may be otherwise
expressly specified in this Credit Agreement. All statements contained in any
certificate or other paper delivered to any Bank or the Agent at any time by or
on behalf of the Borrower or any of the other Transaction Parties pursuant
hereto or in connection with the transactions contemplated hereby shall
constitute representations and warranties by the Borrower or such other
Transaction Party hereunder.

                        19. ASSIGNMENT AND PARTICIPATION.
                            ----------------------------


     19.1. CONDITIONS TO ASSIGNMENT BY BANKS. Except as provided herein, each
Bank may assign to one or more Eligible Assignees all or a portion of its
interests, rights and obligations under this Credit Agreement (including all or
a portion of its Commitment Percentage and Commitment and the same portion of
the Loans at the time owing to it, the Notes held by it and its participating
interest in the risk relating to any Letters of Credit); PROVIDED that (i) each
of the Agent and, unless a Default or Event of Default shall have occurred and
be continuing, the Borrower shall have given its prior written consent to such
assignment, which consent, in the case of the Borrower, will not be unreasonably
withheld, (ii) each such assignment shall be of a constant, and not a varying,
percentage of all the assigning Bank's rights and obligations under this Credit
Agreement, (iii) each assignment shall be in an amount that is a whole multiple
of $5,000,000, (iv) each Bank which is a Bank on the date hereof shall retain,
free of any such assignment, an amount of its Commitment of not less than
$10,000,000 and (v) the parties to such assignment shall execute and deliver to
the Agent, for recording in the Register (as hereinafter defined), an Assignment
and Acceptance, substantially in the form of EXHIBIT D hereto (an "Assignment
and Acceptance"), together with any Notes subject to such assignment. Upon such
execution, delivery, acceptance and recording, from and after the effective date
specified in each Assignment and Acceptance, which effective date shall be at
least five (5) Business Days after the execution thereof, (i) the assignee
thereunder shall be a party hereto and, to the extent provided in such
Assignment and Acceptance, have the rights and obligations of a Bank

<PAGE>   76

                                      -69-


hereunder, and (ii) the assigning Bank shall, to the extent provided in such
assignment and upon payment to the Agent of the registration fee referred to in
[Section]19.3, be released from its obligations under this Credit Agreement.


     19.2. CERTAIN REPRESENTATION AND WARRANTIES; LIMITATIONS; COVENANTS. By
executing and delivering an Assignment and Acceptance, the parties to the
assignment thereunder confirm to and agree with each other and the other parties
hereto as follows:

          (a) other than the representation and warranty that it is the legal
     and beneficial owner of the interest being assigned thereby free and clear
     of any adverse claim, the assigning Bank makes no representation or
     warranty, express or implied, and assumes no responsibility with respect to
     any statements, warranties or representations made in or in connection with
     this Credit Agreement or the execution, legality, validity, enforceability,
     genuineness, sufficiency or value of this Credit Agreement, the other
     Transaction Documents or any other instrument or document furnished
     pursuant hereto or the attachment, perfection or priority of any security
     interest or mortgage,

          (b) the assigning Bank makes no representation or warranty and assumes
     no responsibility with respect to the financial condition of the Borrower
     and the other Transaction Parties or any other Person primarily or
     secondarily liable in respect of any of the Obligations, or the performance
     or observance by the Borrower and the other Transaction Parties or any
     other Person primarily or secondarily liable in respect of any of the
     Obligations of any of their obligations under this Credit Agreement or any
     of the other Loan Documents or any other instrument or document furnished
     pursuant hereto or thereto;

          (c) such assignee confirms that it has received a copy of this Credit
     Agreement, together with copies of the most recent financial statements
     referred to in [Section]7.4 and [Section]8.4 and such other documents and
     information as it has deemed appropriate to make its own credit analysis
     and decision to enter into such Assignment and Acceptance;

          (d) such assignee will, independently and without reliance upon the
     assigning Bank, the Agent or any other Bank and based on such documents and
     information as it shall deem appropriate at the time, continue to make its
     own credit decisions in taking or not taking action under this Credit
     Agreement;

          (e) such assignee represents and warrants that it is an Eligible
     Assignee;

          (f) such assignee appoints and authorizes the Agent to take such
     action as agent on its behalf and to exercise such powers under this Credit
     Agreement and the other Loan Documents as are delegated to the 
<PAGE>   77


                                      -70-


     Agent by the terms hereof or thereof, together with such powers as are
     reasonably incidental thereto;

          (g) such assignee agrees that it will perform in accordance with their
     terms all of the obligations that by the terms of this Credit Agreement are
     required to be performed by it as a Bank;

          (h) such assignee represents and warrants that it is legally
     authorized to enter into such Assignment and Acceptance; and

          (i) such assignee acknowledges that it has made arrangements with the
     assigning Bank satisfactory to such assignee with respect to its PRO RATA
     share of Letter of Credit Fees in respect of outstanding Letters of Credit.


     19.3. REGISTER. The Agent shall maintain a copy of each Assignment and
Acceptance delivered to it and a register or similar list (the "Register") for
the recordation of the names and addresses of the Banks and the Commitment
Percentage of, and principal amount of the Loans owing to and Letter of Credit
Participations purchased by, the Banks from time to time. The entries in the
Register shall be conclusive, in the absence of manifest error, and the
Borrower, the Agent and the Banks may treat each Person whose name is recorded
in the Register as a Bank hereunder for all purposes of this Credit Agreement.
The Register shall be available for inspection by the Borrower and the Banks at
any reasonable time and from time to time upon reasonable prior notice. Upon
each such recordation, the assigning Bank agrees to pay to the Agent a
registration fee in the sum of $3,500.


     19.4. NEW NOTES. Upon its receipt of an Assignment and Acceptance executed
by the parties to such assignment, together with each Note subject to such
assignment, the Agent shall (i) record the information contained therein in the
Register, and (ii) give prompt notice thereof to the Borrower and the Banks
(other than the assigning Bank). Within five (5) Business Days after receipt of
such notice, the Borrower, at its own expense, shall execute and deliver to the
Agent, in exchange for each surrendered Note, a new Note to the order of such
Eligible Assignee in an amount equal to the amount assumed by such Eligible
Assignee pursuant to such Assignment and Acceptance and, if the assigning Bank
has retained some portion of its obligations hereunder, a new Note to the order
of the assigning Bank in an amount equal to the amount retained by it hereunder.
Such new Notes shall provide that they are replacements for the surrendered
Notes, shall be in an aggregate principal amount equal to the aggregate
principal amount of the surrendered Notes, shall be dated the effective date of
such in Assignment and Acceptance and shall otherwise be substantially the form
of the assigned Notes. Within five (5) days of issuance of any new Notes
pursuant to this [Section]19.4, the Borrower shall deliver an opinion of
counsel, addressed to the Banks and the Agent, relating to the due
authorization, execution and delivery of such new Notes and the legality,
validity and binding effect thereof, in form and substance satisfactory to the

<PAGE>   78


                                      -71-


Banks. The surrendered Notes shall be cancelled and returned to the Borrower
within a reasonable time following the issuance of any new Note.


     19.5. PARTICIPATIONS. Each Bank may sell Participations to one or more
banks or other entities in all or a portion of such Bank's rights and
obligations under this Credit Agreement and the other Loan Documents; PROVIDED
that (i) each such participation shall be in an amount of not less than
$5,000,000, (ii) any such sale or participation shall not affect the rights and
duties of the selling Bank hereunder to the Borrower and (iii) the only rights
granted to the participant pursuant to such participation arrangements with
respect to waivers, amendments or modifications of the Loan Documents shall be
the rights to approve waivers, amendments or modifications that would reduce the
principal of or the interest rate on any Loans, extend the term or increase the
amount of the Commitment of such Bank as it relates to such participant, reduce
the amount of any commitment fees or Letter of Credit Fees to which such
participant is entitled or extend any regularly scheduled payment date for
principal or interest.


     19.6. DISCLOSURE. The Borrower agrees that, in addition to disclosures made
in accordance with standard and customary banking practices and in accordance
with the requirements of [Section]28 hereof, any Bank may disclose information
obtained by such Bank pursuant to this Credit Agreement to assignees or
participants and potential assignees or participants hereunder; PROVIDED that
such assignees or participants or potential assignees or participants shall
agree (i) to treat in confidence such information unless such information
otherwise becomes public knowledge, (ii) not to disclose such information to a
third party, except as required by law or legal process and (iii) not to make
use of such information for purposes of transactions unrelated to such
contemplated assignment or participation.


     19.7. ASSIGNEE OR PARTICIPANT AFFILIATED WITH THE BORROWER. If any assignee
Bank is an Affiliate of the Borrower, then any such assignee Bank shall have no
right to vote as a Bank hereunder or under any of the other Loan Documents for
purposes of granting consents or waivers or for purposes of agreeing to
amendments or other modifications to any of the Loan Documents or for purposes
of making requests to the Agent pursuant to [Section]13.1 or [Section]13.2, and
the determination of the Majority Banks shall for all purposes of this Agreement
and the other Loan Documents be made without regard to such assignee Bank's
interest in any of the Loans. If any Bank sells a participating interest in any
of the Loans or Reimbursement Obligations to a participant, and such participant
is the Borrower or an Affiliate of the Borrower, then such transferor Bank shall
promptly notify the Agent of the sale of such participation. A transferor Bank
shall have no right to vote as a Bank hereunder or under any of the other Loan
Documents for purposes of granting consents or waivers or for purposes of
agreeing to amendments or modifications to any of the Loan Documents or for
purposes of making requests to the Agent pursuant to [Section]13.1 or
[Section]13.2 to the extent that such participation is beneficially owned by the
Borrower or any Affiliate of the Borrower, and the determination of the Majority
Banks shall for all purposes of this Agreement and the other Loan Documents be
made without

<PAGE>   79


                                      -72-


regard to the interest of such transferor Bank in the Loans to the extent of
such participation.


     19.8. MISCELLANEOUS ASSIGNMENT PROVISIONS. Any assigning Bank shall retain
its rights to be indemnified pursuant to [Section]16 with respect to any claims
or actions arising prior to the date of such assignment. If any assignee Bank is
not incorporated under the laws of the United States of America or any state
thereof, it shall, prior to the date on which any interest or fees are payable
hereunder or under any of the other Loan Documents for its account, deliver to
the Borrower and the Agent certification as to its exemption from deduction or
withholding of any United States federal income taxes. Anything contained in
this [Section]19 to the contrary notwithstanding, any Bank may at any time
pledge all or any portion of its interest and rights under this Credit Agreement
(including all or any portion of its Notes) to any of the twelve Federal Reserve
Banks organized under [Section]4 of the Federal Reserve Act, 12 U.S.C.
[Section]341. No such pledge or the enforcement thereof shall release the
pledgor Bank from its obligations hereunder or under any of the other Loan
Documents.


     19.9. ASSIGNMENT BY BORROWER. The Borrower shall not assign or transfer any
of its rights or obligations under any of the Loan Documents without the prior
written consent of each of the Banks.

                                20. NOTICES, ETC.
                                    ------------

     Except as otherwise expressly provided in this Credit Agreement, all
notices and other communications made or required to be given pursuant to this
Credit Agreement or the Notes or any Letter of Credit Applications shall be in
writing and shall be delivered in hand, mailed by United States registered or
certified first class mail, postage prepaid, sent by overnight courier, or sent
by telegraph, telecopy, facsimile or telex and confirmed by delivery via courier
or postal service, addressed as follows:

          (a) if to the Borrower, at 12A Manor Parkway, Salem, New Hampshire
     03709, Attention: Timothy P. Losik, or at such other address for notice as
     the Borrower shall last have furnished in writing to the Person giving the
     notice;

          (b) if to the Agent, at 100 Federal Street, Boston, Massachusetts
     02110, USA, Attention: Jeffrey G. Millman, Vice President, or Division
     Executive, or such other address for notice as the Agent shall last have
     furnished in writing to the Person giving the notice; and

          (c) if to any Bank, at such Bank's address set forth on SCHEDULE 1
     hereto, or such other address for notice as such Bank shall have last
     furnished in writing to the Person giving the notice.

     Any such notice or demand shall be deemed to have been duly given or made
and to have become effective (i) if delivered by hand, overnight courier or
facsimile to a responsible officer of the party to which it is directed, at the
time 

<PAGE>   80

                                      -73-


of the receipt thereof by such officer or the sending of such facsimile and (ii)
if sent by registered or certified first-class mail, postage prepaid, on the
third Business Day following the mailing thereof.

                               21. GOVERNING LAW.
                                   -------------

     THIS CREDIT AGREEMENT AND, EXCEPT AS OTHERWISE SPECIFICALLY PROVIDED
THEREIN, EACH OF THE OTHER LOAN DOCUMENTS ARE CONTRACTS UNDER THE LAWS OF THE
COMMONWEALTH OF MASSACHUSETTS AND SHALL FOR ALL PURPOSES BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAWS OF SAID COMMONWEALTH OF MASSACHUSETTS
(EXCLUDING THE LAWS APPLICABLE TO CONFLICTS OR CHOICE OF LAW). THE BORROWER
AGREES THAT ANY SUIT FOR THE ENFORCEMENT OF THIS CREDIT AGREEMENT OR ANY OF THE
OTHER LOAN DOCUMENTS MAY BE BROUGHT IN THE COURTS OF THE COMMONWEALTH OF
MASSACHUSETTS OR ANY FEDERAL COURT SITTING THEREIN AND CONSENTS TO THE
NONEXCLUSIVE JURISDICTION OF SUCH COURT AND SERVICE OF PROCESS IN ANY SUCH SUIT
BEING MADE UPON THE BORROWER BY MAIL AT THE ADDRESS SPECIFIED IN [Section]21.
THE BORROWER HEREBY WAIVES ANY OBJECTION THAT IT MAY NOW OR HEREAFTER HAVE TO
THE VENUE OF ANY SUCH SUIT OR ANY SUCH COURT OR THAT SUCH SUIT IS BROUGHT IN AN
INCONVENIENT COURT.

                                  22. HEADINGS.
                                      --------

     The captions in this Credit Agreement are for convenience of reference only
and shall not define or limit the provisions hereof.

                                23. COUNTERPARTS.
                                    ------------

     This Credit Agreement and any amendment hereof may be executed in several
counterparts and by each party on a separate counterpart, each of which when
executed and delivered shall be an original, and all of which together shall
constitute one instrument. In proving this Credit Agreement it shall not be
necessary to produce or account for more than one such counterpart signed by the
party against whom enforcement is sought.

                           24. ENTIRE AGREEMENT, ETC.
                               ---------------------

     The Loan Documents and any other documents executed in connection herewith
or therewith express the entire understanding of the parties with respect to the
transactions contemplated hereby. Neither this Credit Agreement nor any term
hereof may be changed, waived, discharged or terminated, except as provided in
[Section]26.

<PAGE>   81


                                      -74-


                            25. WAIVER OF JURY TRIAL.
                                --------------------

     The Borrower hereby waives its right to a jury trial with respect to any
action or claim arising out of any dispute in connection with this Credit
Agreement, the Notes or any of the other Loan Documents, any rights or
obligations hereunder or thereunder or the performance of which rights and
obligations. Except as prohibited by law, the Borrower hereby waives any right
it may have to claim or recover in any litigation referred to in the preceding
sentence any special, exemplary, punitive or consequential damages or any
damages other than, or in addition to, actual damages. The Borrower (i)
certifies that no representative, agent or attorney of any Bank or the Agent has
represented, expressly or otherwise, that such Bank or the Agent would not, in
the event of litigation, seek to enforce the foregoing waivers and (ii)
acknowledges that the Agent and the Banks have been induced to enter into this
Credit Agreement and the other Loan Documents to which it is a party by, among
other things, the waivers and certifications contained herein.

                     26. CONSENTS, AMENDMENTS, WAIVERS, ETC.
                         ----------------------------------

     Any consent or approval required or permitted by this Credit Agreement to
be given by all of the Banks may be given, and any term of this Credit
Agreement, the other Loan Documents or any other instrument related hereto or
mentioned herein may be amended, and the performance or observance by the
Borrower or any of the other Transaction Parties of any terms of this Credit
Agreement, the other Loan Documents or such other instrument or the continuance
of any Default or Event of Default may be waived (either generally or in a
particular instance and either retroactively or prospectively) with, but only
with, the written consent of the Borrower and the written consent of the
Majority Banks. Notwithstanding the foregoing, the rate of interest on the Notes
(other than interest accruing pursuant to [Section]5.10.2 following the
effective date of any waiver by the Majority Banks of the Default or Event oF
Default relating thereto), the term of the Notes, the amount of the Commitments
of the Banks, and the amount of commitment fee or Letter of Credit Fees
hereunder may not be changed without the written consent of the Borrower and the
written consent of each Bank affected thereby; the definition of Majority Banks
may not be amended without the written consent of all of the Banks; and the
amount of the Agent's Fee or any Letter of Credit Fees payable for the Agent's
account and [Section]15 may not be amended without the written consent of the
Agent. No waiver shall extend to oR affect any obligation not expressly waived
or impair any right consequent thereon. No course of dealing or delay or
omission on the part of the Agent or any Bank in exercising any right shall
operate as a waiver thereof or otherwise be prejudicial thereto. No notice to or
demand upon the Borrower shall entitle the Borrower to other or further notice
or demand in similar or other circumstances.

                                27. SEVERABILITY.
                                    ------------

     The provisions of this Credit Agreement are severable and if any one clause
or provision hereof shall be held invalid or unenforceable in whole or in

<PAGE>   82

                                      -75-


part in any jurisdiction, then such invalidity or unenforceability shall affect
only such clause or provision, or part thereof, in such jurisdiction, and shall
not in any manner affect such clause or provision in any other jurisdiction, or
any other clause or provision of this Credit Agreement in any jurisdiction.

                               28. CONFIDENTIALITY
                                   ---------------

     Each of the Agent and the Banks agree to keep any information delivered or
made available to it by or on behalf of the Borrower or any of the other
Transaction Parties confidential from anyone other than its employees, officers,
attorneys and other advisors, PROVIDED that nothing herein shall prevent the
Agent or such Bank from disclosing such information upon the order or request of
any court or administrative agency or authority, upon the request or demand of
any regulatory agency or authority, to the extent that such information has been
publicly disclosed other than as a result of a disclosure by the Agent or such
Bank, otherwise as required by law or to any actual or potential assignee or
participant hereof pursuant to [Section]19.6. The Borrower agrees that it will,
and wilL cause each of the other Transaction Parties to, keep any information
delivered or made available to it by or on behalf of the Agent or any of the
Banks (including, without limitation, the amount of any fees payable to the
Agent pursuant to [Section]5.1 and the Agent's Side Letter) confidential from
anyone other that its employees, officers, attorneys and other advisors,
PROVIDED that nothing herein shall prevent the Borrower from disclosing such
information upon the order or request of any court or administrative agency or
authority, upon the request or demand of any regulatory agency or authority, to
the extent that such information has been publicly disclosed other than as a
result of disclosure by the Borrower or any of the other Transaction Parties, or
otherwise as required by law.


<PAGE>   83



     IN WITNESS WHEREOF, the undersigned have duly executed this Credit
Agreement as a sealed instrument as of the date first set forth above.


                                HADCO CORPORATION



                                By: ___________________________________________
                                    Name:
                                    Title:

                                THE FIRST NATIONAL BANK OF BOSTON, 
                                individually and as Agent



                                By: ___________________________________________
                                    Name:
                                    Title:  Vice President