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                        RENEWAL SUB-LINE PROMISSORY NOTE

$8,500,000.00                                                  October 26, 2000

         FOR VALUE RECEIVED, the undersigned, American Technical Ceramics Corp.
(the "Borrower"), a Delaware corporation, hereby promises to pay to the order of
Bank of America, N.A. (the "Bank"), successor to NationsBank, N.A., whose
address is 50 N. Laura Street, Jacksonville, Florida 32202, the principal sum of
Eight Million Five Hundred Thousand and No/100 Dollars ($8,500,000.00), or such
other principal amount as may be disbursed from time to time pursuant to Section
1.02 of the Loan Agreement (as defined herein), together with interest on the
outstanding principal balance hereof from the date of disbursement until payment
in full at the rate provided herein. This Note shall be governed by the
following provisions:

         1.       Loan Agreement. The Borrower and the Bank have executed an
Amended and Restated Loan Agreement (as amended or restated from time to time,
the "Loan Agreement") dated November 25, 1998. The loan evidenced by this Note
shall be a revolving loan, and the Borrower may borrow, repay and reborrow
principal amounts hereunder subject to the terms contained herein and in the
Loan Agreement. Notwithstanding the foregoing: (a) the outstanding principal
balance hereof shall not exceed $8,500,000 at any one time (or such lesser
amount as may be set forth in the Loan Agreement); and (b) the Borrower shall
not in any event be entitled to obtain further advances hereunder on or after
the expiration of the Revolving Period (as defined in the Loan Agreement). This
Note is the Sub-Line Note described in the Loan Agreement.

         2.       Payments.

                  (a) The Borrower shall pay all accrued interest hereunder on
         the first day of each January, April, July and October during the term
         hereof.

                  (b) The Borrower shall pay all outstanding principal
         hereunder, together with all then accrued and unpaid interest
         hereunder, at the expiration of the Revolving Period (as defined in the
         Loan Agreement) (except to the extent that such principal amounts have
         been rolled into a Term Note (as defined in the Loan Agreement)
         pursuant to the terms of the Loan Agreement on or before such date).

         3.       Interest.

                  (a) Interest shall initially accrue on the outstanding
         principal balance of this Note at a rate that is equal to the Adjusted
         Libor Rate (as defined herein) in effect as of the date hereof. The
         rate of interest shall be adjusted on each Interest Rate Adjustment
         Date (as defined herein) so that interest shall accrue at the Adjusted
         Libor Rate for the Interest Period (as defined herein) commencing on
         such Interest Rate Adjustment Date. For purposes hereof, the following
         terms shall have the following meanings:


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                           (i) "Adjusted Libor Rate" for each Interest Period
                  shall mean a rate that is equal to the applicable Libor Rate
                  plus 1.5% per annum. The Libor Rate for each Interest Period
                  shall mean the offered rate for deposits in United States
                  dollars in the London Interbank market for a one month period
                  which appears on the Libor Rate Reference Page (as defined
                  herein) as of 11:00 a.m. (London time) on the day that is two
                  London Banking Days (as defined herein) preceding the first
                  Banking Business Day (as defined herein) of the Interest
                  Period. If at least two such offered rates appear on the Libor
                  Rate Reference Page, the rate will be the arithmetic mean of
                  such offered rates. The Bank may, in its discretion, use rate
                  quotations for a 30 day period in lieu of quotations for a
                  substantially equivalent one month period.

                           (ii) "Banking Business Day" shall mean each day other
                  than a Saturday, a Sunday or any holiday on which commercial
                  banks in Jacksonville, Florida are closed for business.

                           (iii) "Interest Period" shall mean: (aa) an initial
                  period commencing on the date hereof and continuing through
                  the day immediately preceding the first Interest Rate
                  Adjustment Date; and (bb) each period thereafter commencing on
                  each Interest Rate Adjustment Date and continuing through the
                  day immediately preceding the next Interest Rate Adjustment
                  Date.

                           (iv) "Interest Rate Adjustment Date" shall mean the
                  first day of each calendar month during the term hereof.

                           (v) "Libor Rate Reference Page" shall mean any of the
                  following reference pages or sources (as selected from time to
                  time by the Bank in its discretion): (aa) the Reuters Screen
                  LIBO Page; (bb) the Dow Jones Telerate Page 3750; or (cc) if
                  the Bank is unable to obtain rates pursuant to the foregoing
                  clauses (aa) or (bb), such other index or source as the Bank
                  may reasonably select showing rates offered for United States
                  dollar deposits in the London Interbank market.

                           (vi) "London Banking Day" shall mean each day other
                  than a Saturday, a Sunday or any holiday on which commercial
                  banks in London, England are closed for business.

                  (b) Interest  shall be  calculated  on the basis of a 360 day
         year (based upon the actual number of days elapsed).

                  (c) The total liability of the Borrower and any endorsers or
         guarantors hereof for payment of interest shall not exceed any
         limitations imposed on the payment of interest by applicable usury
         laws. If any interest is received or charged by any holder hereof in
         excess of that amount, the Borrower shall be entitled to an immediate
         refund of the excess.


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                  (d) Upon the occurrence of an Event of Default hereunder,
         interest shall accrue at the Default Rate hereinafter set forth
         notwithstanding the provisions of this section.

         4.       Prepayment. The Borrower shall be entitled to prepay this Note
in whole or in part at any time without penalty.

         5.       Application of Payments. All payments hereunder shall be
applied first to the Bank s costs and expenses payable under the Loan Agreement
or hereunder, then to fees authorized hereunder or under the Loan Agreement,
then to interest and then to principal.

         6.       Default. Any Event of Default under the Loan Agreement shall
be considered an "Event of Default" hereunder. If any Default (as defined in the
Loan Agreement) shall occur, any obligation of the Bank to make advances
hereunder shall be terminated without notice to the Borrower. In addition, if
any Event of Default shall occur, the outstanding principal of this Note, all
accrued and unpaid interest hereunder and all other amounts payable under this
Note shall be and become, in the manner and as provided in the Loan Agreement,
forthwith due and payable, without presentment, demand, protest or further
notice of any kind, all of which are hereby expressly waived by the Borrower.
Upon the occurrence of any Event of Default, the outstanding principal of this
Note, and any accrued and unpaid interest, shall bear interest at a rate of
either four percent (4%) per annum above the Prime Rate after default until paid
or, if such rate is usurious under the laws of Florida, then at the highest
legal rate permissible thereunder (the "Default Rate"). For purposes hereof, the
"Prime Rate" shall mean the rate of interest announced from time to time by the
Bank (or any successor thereto) as its prime rate. The Default Rate shall change
on each day that the Prime Rate changes.

         7.       Expenses. The Borrower agrees to pay the Bank all costs
incurred by it in connection with the collection of this Note. Such costs
include, without limitation, reasonable fees for the services of counsel and
legal assistants employed to collect this Note, whether or not suit be brought,
and whether incurred in connection with collection, trial, appeal or otherwise.
The Borrower further agrees to indemnify and hold the Bank harmless against
liability for the payment of state documentary stamp taxes, intangible taxes or
other taxes (including interest and penalties, if any), excluding income or
service taxes of the Bank, which may be determined to be payable with respect to
this transaction.

         8.       Late Charge. If any scheduled payment hereunder is 15 or more
days late, the Borrower shall pay a fee equal to 4% of the unpaid portion of the
scheduled payment. The fee is not a penalty, but liquidated damages to defray
administrative and related expenses due to such late payment. The fee shall be
immediately due and payable and shall be paid by the Borrower to the Bank
without notice or demand. This provision for a fee is not and shall not be
deemed a grace period, and Bank has no obligation to accept a late payment.
Further, the acceptance of a late payment shall not constitute a waiver of any
default then existing or thereafter arising under this Note.


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         9.       Setoffs. The Borrower hereby grants to the Bank a continuing
first lien security interest in any and all money, general or specific deposits,
or property of the Borrower now or hereafter in the possession of the Bank. The
Borrower authorizes and empowers the Bank, in its sole discretion, at any time
after the occurrence of a default hereunder to appropriate and, in such order as
the Bank may elect, apply any such money, deposits or property to the payment
hereof or to the payment of any and all indebtedness, liabilities and
obligations of the Borrower to the Bank or any of the Bank s affiliates, whether
now existing or hereafter created or arising or now owned or howsoever after
acquired by the Bank or any of the Bank s affiliates (whether such indebtedness,
liabilities and obligations are or will be joint or several, direct or indirect,
absolute or contingent, liquidated or unliquidated, matured or unmatured,
including, but not limited to, any letter of credit issued by the Bank for the
account of the Borrower).

         10.      Auto Debit. The Borrower hereby authorizes the Bank to
automatically deduct the amount of any payment due hereunder from any of the
Borrower's accounts now or hereafter maintained with the Bank (including,
without limitation, account number 2171045294). If the funds in such account are
insufficient to cover any payment, the Bank shall not be obligated to advance
funds to cover the payment.

         11.      Miscellaneous. The Borrower and all sureties, endorsers and
guarantors of this Note shall make all payments hereunder in lawful money of the
United States at the Bank s address set forth herein or at such other place as
the Bank may designate in writing. The remedies of the Bank as provided herein
shall be cumulative and concurrent, and may be pursued singly, successively or
together, at the sole discretion of the Bank and may be exercised as often as
occasion therefor shall arise. No act of omission or commission of the Bank,
including specifically any failure to exercise any right, remedy or recourse,
shall be effective, unless set forth in a written document executed by the Bank,
and then only to the extent specifically recited therein. A waiver or release
with reference to one event shall not be construed as continuing, as a bar to,
or as a waiver or release of any subsequent right, remedy or recourse as to any
subsequent event. This Note shall be construed and enforced in accordance with
Florida law and shall be binding on the successors and assigns of the parties
hereto. The term "Bank" as used herein shall mean Bank of America, N.A. and its
successors and permitted assignees under the Loan Agreement. The Bank may, at
its option, round any or all fractional interest rates under paragraph 3 upwards
to the next higher 1/100 of 1%. The Borrower hereby: (i) waives demand, notice
of demand, presentment for payment, notice of nonpayment or dishonor, protest,
notice of protest and all other notice, filing of suit and diligence in
collecting this Note, or in the Bank s enforcing any of its rights under any
guaranties securing the repayment hereof; (ii) agrees to any substitution,
addition or release of or any party or person primarily or secondarily liable
hereon; (iii) agrees that the Bank shall not be required first to institute any
suit, or to exhaust its remedies against the Borrower or any other person or
party to become liable hereunder, or against any collateral in order to enforce
payment of this Note; and (iv) agrees that, notwithstanding the occurrence of
any of the foregoing (except with the express written release by the Bank of the
Borrower), the Borrower shall be and remain directly and primarily, liable for
all sums due under this Note.


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         12.      NOTICE OF FINAL AGREEMENT. THIS WRITTEN PROMISSORY NOTE
REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED
BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OR
UNDERSTANDINGS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN
THE PARTIES.

                                    AMERICAN TECHNICAL CERAMICS CORP.


                                    By:
                                        ----------------------------------
                                        Kathleen M. Kelly
                                        Vice President - Administration

                                                (CORPORATE SEAL)



STATE OF NEW YORK
COUNTY OF SUFFOLK

         The foregoing instrument was executed, acknowledged and delivered
before me this ____ day of October, 2000, by Kathleen M. Kelly, the Vice
President - Administration of American Technical Ceramics Corp., on behalf of
the corporation, in Suffolk County, New York.



                                    ------------------------------------------
                                    Notary Public, State and County
                                    Aforesaid
                                    Print Name:
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                                    My commission expires:
                                                          --------------------
                                    My commission number:
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                                    (NOTARIAL SEAL)



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