<PAGE>

                                                                  EXHIBIT 10(yy)

                       THIRD AMENDMENT TO CREDIT AGREEMENT
                             AND SECOND AMENDMENT TO
                     US PLEDGE AGREEMENT AND ACKNOWLEDGMENT

            THIRD AMENDMENT TO CREDIT AGREEMENT AND SECOND AMENDMENT TO US
PLEDGE AGREEMENT AND ACKNOWLEDGMENT (this "Amendment"), dated as of January 26,
2001, among THE ALPINE GROUP, INC. (the "Borrower"), the lenders party to the
Credit Agreement referred to below (the "Lenders"), FLEET NATIONAL BANK
(formerly known as Fleet Bank, N.A.), as Syndication Agent (the "Syndication
Agent"), BANK OF AMERICA, N.A., as Documentation Agent (the "Documentation
Agent"), and BANKERS TRUST COMPANY ("BTCo"), as Administrative Agent (in such
capacity, the "Administrative Agent"). All capitalized terms used herein and not
otherwise defined shall have the respective meanings provided such terms in the
Credit Agreement referred to below.

                              W I T N E S S E T H :

            WHEREAS, the Borrower, the Lenders, the Documentation Agent, the
Syndication Agent and the Administrative Agent are parties to a Credit
Agreement, dated as of November 23, 1999 (the "Credit Agreement");

            WHEREAS, the Borrower and BTCo, as Pledgee, are parties to a US
Pledge Agreement, dated as of November 23, 1999 (the "US Pledge Agreement"); and

            WHEREAS, subject to the terms and conditions of this Amendment, the
parties hereto wish to amend the Credit Agreement and the US Pledge Agreement as
follows;

            NOW, THEREFORE, it is agreed:

            1. (a) Notwithstanding anything to the contrary contained in Section
9.06 (or elsewhere) of the Credit Agreement or in any Credit Documents, the
Lenders hereby agree that, with respect to the Cookson Shares owned by the
Borrower on the Third Amendment Effective Date (as defined below) (and any
Cookson Shares delivered in substitution or replacement thereof, or representing
dividends, distributions or rights issues with respect to said Cookson Shares),
the Borrower may from time to time enter into one or more Cookson Derivative
Transactions, and the Lenders hereby agree that, in connection with each Cookson
Derivative Transaction, a number of Cookson Shares equal to the Aggregate Put
Number of Cookson Shares subject to the respective Cookson Derivative
Transaction shall be released (following a timely request from the Borrower)
from the security interests created pursuant to the UK Pledge Agreement and any
other Lien created by the other Credit Documents in accordance with the
procedures set forth in immediately succeeding clause (b) so long as:
<PAGE>

            (i)   the requirements set forth in the definition of Cookson
                  Derivative Transaction are satisfied with respect to the
                  Cookson Shares being so released;

            (ii)  contemporaneously with each such release the Borrower shall
                  (x) incur Cookson Facility Loans under the Cookson Facility in
                  an aggregate principal amount not less than 85% of the
                  respective Aggregate Put Strike Price (calculated on the date
                  of the applicable Cookson Confirmation, which Cookson
                  Confirmation shall be dated no earlier than three Business
                  Days prior to the incurrence of such Cookson Facility Loans,
                  except that such three Business Day period shall be extended
                  by up to ten additional Business Days to the extent that the
                  Borrower has not timely delivered to, or timely received from,
                  Deutsche all ordinary course documentation required in
                  connection with the incurrence of Cookson Facility Loans,
                  i.e., notes, notices of borrowing and the like, or if for any
                  other reason there is a delay in making the respective Cookson
                  Facility Loans; provided that in any event the Cookson
                  Facility Loans as contemplated above must be incurred
                  contemporaneously with the respective release) applicable to
                  the Cookson Shares so released and not be in excess of the
                  Aggregate Put Strike Price applicable to the Cookson Shares so
                  released and (y) apply an amount equal to 100% of the Dollar
                  Equivalent (as determined on such date) of the aggregate
                  principal amount of such Cookson Facility Loans to repay then
                  outstanding Loans as (and to the extent) required pursuant to
                  Section 4.02(f) of the Credit Agreement;

            (iii) the Total Commitment is permanently reduced as (and to the
                  extent) required pursuant to Section 3.03(b)(ii) of the Credit
                  Agreement;

            (iv)  no Event of Default shall be in existence on the date of the
                  respective release of Cookson Shares (including immediately
                  after giving effect to the respective release and any
                  corresponding repayment of Loans pursuant to Section 4.02(f)
                  of the Credit Agreement) or, even if there is or would then be
                  an Event of Default (other than an Event of Default as
                  described in following clause (v) of this Section 1), such
                  release date is within 8 Business Days (which 8 Business Day
                  period shall be extended by up to ten additional Business Days
                  to the extent that the Borrower has not timely delivered to,
                  or timely received from, Deutsche all ordinary course
                  documentation required in connection with the incurrence of
                  Cookson Facility Loans, i.e. notes, notice of borrowing and
                  the like, or if for any other reason there is a delay in
                  making the respective Cookson Facility Loans) of the first
                  date on which Deutsche entered into one or more short sales in
                  respect of the Cookson Shares to be released as part of the
                  respective Cookson Derivative Transaction, and no Event of
                  Default shall have been in existence on the date any such
                  short sale was entered into by Deutsche as part of the
                  respective Cookson Derivative Transaction (both before and
                  immediately after giving effect to the respective short
                  sales);


                                      -2-
<PAGE>

            (v)   no Default or Event of Default with respect to the Borrower
                  shall exist pursuant to Section 10.05 of the Credit Agreement
                  on the date of the respective release of Cookson Shares;

            (vi)  on the date of each short sale in connection with a given
                  Cookson Derivative Transaction, the Borrower and/or Deutsche
                  shall have determined that, with respect to all short sales
                  which have theretofore occurred (including the short sale then
                  being made) during the relevant Cookson Derivative Transaction
                  Period, if an amount equal to the minimum required Aggregate
                  Put Strike Price (determined in accordance with the definition
                  of Put Strike Price contained herein) was in fact received by
                  the Borrower as proceeds of Cookson Facility Loans with
                  respect to the number of Cookson Shares theretofore sold short
                  during the respective Cookson Derivative Transaction Period
                  multiplied by the Relevant Multiplier and if the Dollar
                  Equivalent thereof had in fact been used to pay down Loans to
                  the extent required by Section 4.02(f) of the Credit
                  Agreement, then the Borrower would still have remained in
                  compliance with Section 9.07 of the Credit Agreement as
                  calculated on a pro forma basis as if the respective
                  applications had occurred on the date of the respective short
                  sale; and

            (vii) the Administrative Agent and the Collateral Agent shall have
                  received an officer's certificate of the Borrower
                  substantially in the form annexed hereto as Annex A
                  (appropriately completed to the reasonable satisfaction of the
                  Administrative Agent and Collateral Agent) certifying to the
                  Administrative Agent and the Collateral Agent its compliance
                  with the conditions set forth above in this Section 1 and
                  attaching a copy of the relevant Cookson Confirmation with
                  respect to such Cookson Derivative Transaction and certifying
                  the amount of Cookson Facility Loans being incurred on the
                  date of release of the related Cookson Shares and showing in
                  reasonable detail its compliance with the requirements of
                  preceding clauses (ii) and (iii).

            (b) Subject to the foregoing requirements set forth in preceding
clause (a), the Aggregate Put Number of Cookson Shares the subject of the
relevant Cookson Derivative Transaction shall be released from the security
interest created therein pursuant to the UK Pledge Agreement and the other
Credit Documents, in each case in accordance with the following procedures:

            (i)   Deutsche and the Borrower shall from time to time determine
                  the maximum number of the Available Cookson Shares with
                  respect to which the Borrower and Deutsche may enter into
                  Cookson Derivative Transactions, it being understood and
                  agreed that in no event shall the Aggregate Put Number of
                  Cookson Shares subject to all Cookson Derivative Transactions
                  exceed the aggregate number of Available Cookson Shares;


                                      -3-
<PAGE>

            (ii)  thereafter, Deutsche may commence executing short sales in
                  respect of such Available Cookson Shares. No later than 5:00
                  P.M. (New York time) on the next Business Day following any
                  day on which such short sales have been executed by Deutsche,
                  Deutsche will notify the Administrative Agent of the number of
                  Available Cookson Shares sold short on such day, together with
                  the aggregate amount of short sales of Available Cookson
                  Shares during the applicable Cookson Derivative Transaction
                  Period and the Relevant Multiplier for such Cookson Derivative
                  Transaction Period. At the end of each Cookson Derivative
                  Transaction Period, Deutsche will deliver to the Borrower a
                  Cookson Confirmation in respect of all Available Cookson
                  Shares the subject of the Cookson Derivative Transactions
                  taking place during such Cookson Derivative Transaction
                  Period; and

            (iii) Deutsche will, so long as there is a contemporaneous release
                  of the Cookson Shares subject to the respective Cookson
                  Derivative Transaction as contemplated by preceding clause
                  1(a), within three Business Days (except that such three
                  Business Days may be extended to the extent that the Borrower
                  or Deutsche has not completed all ordinary course
                  documentation required in connection with the incurrence of
                  Cookson Facility Loans, i.e. notes, notices of borrowing and
                  the like) from the date the applicable Cookson Confirmation is
                  delivered as contemplated in clause (b)(ii) above, lend an
                  amount of Pounds Sterling not less than 85% of the applicable
                  Aggregate Put Strike Price (calculated on the date of the
                  applicable Cookson Confirmation). Promptly after such loan is
                  made by Deutsche, the Collateral Agent will promptly deliver
                  to Deutsche (to the extent then pledged pursuant to the UK
                  Pledge Agreement or other relevant Credit Document) a number
                  of Cookson Shares equal to the Aggregate Put Number as
                  determined for the respective Cookson Derivative Transaction.

            So long as the requirements set forth in preceding clauses (a) and
(b) have been satisfied, it is further understood and agreed that,
notwithstanding anything to the contrary contained elsewhere in the Credit
Agreement or the other Credit Documents, the Available Cookson Shares from time
to time released in accordance with this Section 1 in connection with one or
more Cookson Derivative Transactions may in fact be sold (or used for
settlement) pursuant to the relevant Put Options and Call Options (each as
defined in the Master Option Agreement) entered into as contemplated by the
definition of Cookson Derivative Transaction, and such Available Cookson Shares
may, subject to agreements entered into between Borrower and Deutsche (or its
affiliates), from time to time be loaned to Deutsche (and or one more of its
affiliates) and such Available Cookson Shares (and any proceeds thereof) may be
pledged, and delivered for pledge, pursuant to the Pledge and Security Annex (as
defined in the Master Option Agreement).


                                      -4-
<PAGE>

            It is understood and agreed that in connection with any release of
Cookson Shares from the security interests created pursuant to the UK Pledge
Agreement (and any other Credit Document) as contemplated above, the Collateral
Agent is hereby directed by the Lenders to take such actions as it may determine
are reasonably necessary to effectuate such releases (including by directing any
depositary with whom Cookson Shares have been deposited on the Relevant System
(as defined in the UK Pledge Agreement) to release such Cookson Shares), and
that any such release of Cookson Shares from the pledge pursuant to the UK
Pledge Agreement shall be deemed to have been a release at the direction of the
Lenders within the meaning of Section 20.1(b) of the UK Pledge Agreement.
Without limiting the foregoing, it is understood and agreed that the Collateral
Agent, in its discretion, may agree for the benefit of Deutsche that shares
released in accordance with the foregoing requirements of the this Section 1 are
held by it for the benefit of Deutsche (rather than the Lenders). Neither the
Administrative Agent nor the Collateral Agent shall have any liability to the
Lenders for any actions taken by it (in the absence of gross negligence or
willful misconduct) in connection with the releases pursuant to this Section 1
and, in connection therewith, both the Administrative Agent and the Collateral
Agent shall be entitled to conclusively rely on the officer's certificate
delivered pursuant to Section 1(a)(vii) in releasing any Cookson Shares.

            (c) The Borrower represents, warrants, covenants and agrees that no
release of Cookson Shares requested by it pursuant to this Section 1 shall cause
any violation (by the Borrower or any Lender) of Regulation U.

            2. Clause (b) of Section 3.03 of the Credit Agreement is hereby
deleted in its entirety and the following new clause (b) is inserted in lieu
thereof:

            "(b)(i) In addition to any other mandatory commitment reductions
      pursuant to this Section 3.03, on each day after the Third Amendment
      Effective Date on which the Borrower receives any cash proceeds from any
      sale of Shares (other than (x) sales of Superior Option Shares or (y)
      sales of Cookson Shares no longer pledged pursuant to the UK Pledge
      Agreement which are the subject of Cookson Derivative Transactions entered
      into in accordance with the requirements of Section 1 of the Third
      Amendment) or PolyVision Shares, the Total Commitment shall be permanently
      reduced on such date by an amount equal to 100% of the Net (Taxes and
      Sales Commissions) Proceeds from such sale.

            (ii) In addition to any other mandatory commitment reductions
      pursuant to this Section 3.03, on each date after the Third Amendment
      Effective Date on which the Borrower incurs any Cookson Facility Loans
      under the Cookson Facility, the Total Commitment shall concurrently be
      reduced in an amount equal to the Dollar Equivalent of the aggregate
      principal amount of Cookson Facility Loans so incurred."

            3. Clause (c) of Section 3.03 of the Credit Agreement is hereby
amended by deleting the text "Effective Date" appearing in the parenthetical
contained in such clause (c) and inserting in lieu thereof the text "Third
Amendment Effective Date".


                                      -5-
<PAGE>

            4. Clause (d) of Section 3.03 of the Credit Agreement is hereby
deleted in its entirety and the following new clause (d) is inserted in lieu
thereof:

            "(d) In addition to any other mandatory commitment reductions
pursuant to this Section 3.03, on each date on or after the Third Amendment
Effective Date on which the Borrower receives any cash proceeds from any equity
issuance (including the issuance of any options for equity) or capital
contributions, the Total Commitment shall be permanently reduced on such date by
an amount equal to 100% of the cash proceeds of such capital contribution or
sale or issuance (net of underwriting or placement discounts and commissions and
other costs and expenses associated therewith)."

            5. Clause (i) of Section 3.03 of the Credit Agreement is hereby
deleted in its entirety and the following new clause (i) is inserted in lieu
thereof:

            (i)(a) In addition to any other mandatory commitment reductions
      pursuant to this Section 3.03, on each date on or after the Third
      Amendment Effective Date on which the Borrower receives cash proceeds from
      any sale of PolyVision Shares, the Total Commitment shall be permanently
      reduced on such date by an amount equal to 100% of the Net (Taxes and
      Sales Commissions) Proceeds from such sale.

            (b) In addition to any other mandatory commitment reductions
      pursuant to this Section 3.03, on June 30, 2001, to the extent that any
      funds (including the amount of all investments made with funds on deposit
      therein) are then on deposit in the Escrow Account (with the aggregate
      amount thereof being herein called the "Escrow Residual Amount"), the
      Total Commitment shall be permanently reduced on each such date by an
      amount equal to 100% of the Escrow Residual Amount."

            6. Section 3.03 of the Credit Agreement is hereby further amended by
inserting the following new clauses (j) and (k) immediately following clause (i)
of such Section:

            "(j) In addition to any other mandatory commitment reductions
      pursuant to this Section 3.03, on the Third Amendment Effective Date, the
      Total Commitment shall be permanently reduced by an amount such that
      immediately after giving effect to such reduction the Total Unutilized
      Commitment shall be equal to $3,500,000. Contemporaneously with the
      permanent reduction to the Total Commitment pursuant to the immediately
      preceding sentence, each Lender's Commitment shall be permanently reduced
      by an amount equal to the product of (x) such Lender's Percentage
      (calculated immediately prior to the operation of the immediately
      preceding sentence) and (y) an amount equal to the reduction to the Total
      Commitment pursuant to the immediately preceding sentence. Promptly
      following such permanent reduction to the Total Commitment and such
      permanent reductions to each Lender's Commitment, the Administrative Agent
      shall notify the Borrower and each Lender of the new Total Commitment and
      the new Commitment of each Lender, provided that the reductions to the
      Total Commitment and the Commitment of each Lender required pursuant to
      this clause (j) shall be made on the Third Amendment Effective Date
      regardless of any failure of the Administrative Agent to provide such
      notice.


                                      -6-
<PAGE>

            (k) In addition to any other mandatory commitment reductions
      pursuant to this Section 3.03, on each date when the Borrower voluntarily
      prepays any Loans the Total Commitment shall be reduced on such date by an
      amount equal to such prepayment."

            7. Section 7.08(a) of the Credit Agreement is hereby amended by
deleting the period appearing at the end of such subsection (a) and inserting in
lieu thereof the text ", provided that no proceeds from Revolving Loans may be
used to repay Indebtedness except for Indebtedness arising under the Credit
Documents."

            8. Clauses (e) through (h), inclusive, of Section 4.02 of the Credit
Agreement are hereby deleted in their entirety and the following new clauses (e)
through (i) are inserted in lieu thereof:

            "(e) In addition to any other mandatory repayments pursuant to this
      Section 4.02, on each date on or after the Third Amendment Effective Date
      on which the Borrower receives cash proceeds from any sale of any Shares
      (other than sales of Cookson Shares no longer pledged pursuant to the UK
      Pledge Agreement which are the subject of Cookson Derivative Transactions
      entered into in accordance with the requirements of Section 1 of the Third
      Amendment) or PolyVision Shares, an amount equal to 100% of the Net (Taxes
      and Sales Commissions) Proceeds therefrom shall be applied on such date as
      a mandatory repayment of principal of Loans and/or to cash collateralize
      outstanding Letters of Credit, as provided in Section 4.02(h).

            (f) On each day the Borrower actually receives proceeds from Cookson
      Facility Loans, the Borrower shall concurrently with the receipt of such
      proceeds prepay the principal of outstanding Loans and/or cash
      collateralize outstanding Letters of Credit, as provided in Section
      4.02(h), in an amount equal to the Dollar Equivalent of the aggregate
      amount of such proceeds.

            (g) In addition to any other mandatory repayments pursuant to this
      Section 4.02, on June 30, 2001, an amount equal to 100% of the Escrow
      Residual Amount, if any, shall be applied as a mandatory repayment of
      principal of Loans and/or to cash collateralize outstanding Letters of
      Credit as provided in Section 4.02(h).

            (h) Any prepayment required by Sections 4.02(c), (e), (f), (g) and
      (i) shall be applied (i) first, to prepay outstanding Swingline Loans,
      (ii) second, to prepay outstanding Revolving Loans and (iii) third, to the
      extent all Loans have been prepaid in full, to cash collaterize
      outstanding Letters of Credit."

            (i) In addition to any other mandatory repayments pursuant to this
      Section 4.02, on each date on or after the Third Amendment Effective Date
      upon which the Borrower receives any cash proceeds from any equity
      issuance (including the issuance of any options for equity) or capital
      contributions, an amount equal to 100% of the cash proceeds of such
      capital contribution or sale or issuance (net of underwriting or placement
      discounts and commissions and other costs and expenses associated
      therewith) shall be applied on such date in accordance with the
      requirements of Sections 4.02(h).


                                      -7-
<PAGE>

            9. Section 9.01 of the Credit Agreement is hereby amended by (x)
deleting clause (ii) thereof in its entirety and (y) inserting the following new
clause (ii) in lieu thereof:

            "(ii) with respect to any Cookson Shares released from the UK Pledge
      Agreement in accordance with the requirements of Section 1 of the Third
      Amendment (and any Cookson Shares issued in substitution or exchange
      therefor, or constituting distributions, dividends or rights issues
      received with respect thereto), Liens may exist with respect to such
      Cookson Shares (but not any Cookson Shares then pledged pursuant to the UK
      Pledge Agreement) pursuant to, and in accordance with the terms of, the
      Cookson Derivative Transaction Documents."

            10. Section 9.03 of the Credit Agreement is hereby deleted in its
entirety and the following new Section 9.03 is hereby inserted in lieu thereof:
            "9.03 Dividends. The Borrower will not authorize, declare or pay any
Dividends (other than Dividends payable solely in common stock of Borrower)."

            11. Section 9.04 of the Credit Agreement is hereby amended by (i)
deleting the word "and" appearing at the end of clause (v) thereof, (ii)
deleting clause (vi) thereof in its entirety and (iii) inserting the following
new clauses (vi), (vii) and (viii) in lieu thereof:

            "(vi) Indebtedness of the Borrower constituting Cookson Facility
      Loans incurred from time to time pursuant to the Cookson Facility, so long
      as the aggregate principal amount thereof at no time outstanding exceeds
      the lesser of (x) $50 million (it being understood and agreed that, so
      long as the Dollar Equivalent of all outstanding Cookson Facility Loans as
      determined on the date of each incurrence of Cookson Facility Loans
      (taking the Dollar Equivalent of all Cookson Facility Loans theretofore
      incurred as well as the Cookson Facility Loans then being incurred, with
      such Dollar Equivalent being determined on the date of the respective
      incurrence) does not exceed $50 million, the provisions of preceding
      clause (x) shall not be violated as a result of the $50 million threshold
      being exceeded solely as a result of subsequent fluctuations in exchange
      rates between Dollars and Pounds Sterling) and (y) an amount equal to the
      Aggregate Put Strike Prices of all Available Cookson Shares then subject
      to Put Options entered into as part of, and in accordance with the
      definition of, Cookson Derivative Transaction contained herein (with
      respect to which the Valuation Dates as defined in the Master Option
      Agreement have not yet occurred);

            (vii) Indebtedness (not for borrowed money) which may be deemed to
      exist as a result of the existence of the Put Options and Call Options
      entered into with respect to (and constituting part of) one or more
      Cookson Derivative Transactions, in each case so long as the respective
      Cookson Derivative Transaction constitutes a bona fide hedging activity
      and is not speculative in nature; and

            (viii) additional unsecured Indebtedness incurred by the Borrower in
      an aggregate principal amount not to exceed $3,000,000 at any time
      outstanding.


                                      -8-
<PAGE>

            12. Section 9.05 of the Credit Agreement is hereby amended by (i)
inserting the text "or any Cookson Derivative Transaction Document (or any
related document), in each case" immediately following the text "Senior Note
Document" appearing therein and (ii) deleting the reference to "(x)" appearing
therein.

            13. Clause (a) of Section 9.06 of the Credit Agreement is hereby
deleted in its entirety and the following new clause (a) is inserted in lieu
thereof:

            "(a) sell or agree to sell any Shares, in either such case which
      would, at the time of any such agreement or after the consummation of any
      such sale, result in an Event of Default, provided that (i) in the case of
      any sale of Shares (other than sales of Cookson Shares no longer pledged
      pursuant to the UK Pledge Agreement which are the subject of Cookson
      Derivative Transactions entered into in accordance with the requirements
      of Section 1 of the Third Amendment) in compliance with this clause (a),
      (x) 100% of the consideration therefor shall be in cash, paid to the
      Borrower at the closing of such sale and in an amount equal to at least
      the fair market value (based on the definition of "Value" contained in
      Section 11 or, in the case of a sale of Cookson Shares, based on the
      trading price determined by reference to the London Stock Exchange Daily
      Official List) of the Shares the subject of such sale and (y) the Net
      (Taxes and Sales Commissions) Proceeds from any such sale shall be applied
      as a mandatory permanent reduction to the Total Commitment as (and to the
      extent) provided in Section 3.03(b)(i) and to contemporaneously repay
      outstanding Loans or cash collateralize outstanding Letters of Credit
      pursuant to Section 4.02(e) and (ii) sales of Cookson Shares no longer
      pledged pursuant to the UK Pledge Agreement which are the subject of
      Cookson Derivative Transactions entered into in accordance with the
      requirements of Section 1 of the Third Amendment shall be permitted
      notwithstanding anything to the contrary contained above in this clause
      (a)."

            14. Section 9.06 of the Credit Agreement is hereby further amended
by (i) inserting the word "or" at the end of clause (b) thereof, (ii) deleting
the text "; or" at the end of clause (c) thereof and inserting a period in lieu
thereof, (iii) deleting clause (d) in its entirety and (iv) inserting the
following new sentence immediately at the end of said Section 9.06:

            "The parties hereto acknowledge and agree that the occurrence of
      Cookson Derivative Transactions in accordance with the requirements of the
      Third Amendment are the functional equivalent of a sale of the underlying
      Cookson Shares and hereby agree that, for all purposes of this Agreement
      (except for purposes of Section 3.03(b)(i), since such transaction is
      subject to the express requirements of Section 3.03(b)(ii)) and each other
      Credit Document, at the time of the consummation of each Cookson
      Derivative Transaction in accordance with the requirements of the Third
      Amendment, a number of Cookson Shares equal to the Aggregate Put Number of
      Cookson Shares subject to the respective Cookson Derivative Transaction
      shall be deemed to have been sold by the Borrower in a sale permitted by
      this Section 9.06 on the date of its receipt of the Cookson Facility Loan
      proceeds in at least the amount required with respect to such Cookson
      Derivative Transaction pursuant to Section 1(a)(ii) of the Third
      Amendment.".


                                      -9-
<PAGE>

            15. Section 9.07 of the Credit Agreement is hereby deleted in its
entirety and the following new Section 9.07 is inserted in lieu thereof:

            "9.07 Asset Coverage Ratio. The Borrower shall not permit the Asset
Coverage Ratio at any time during a period set forth below to fall below the
ratio set forth opposite such period:

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

             From the Third Amendment
             Effective Date through and
             including January 30, 2001              1.80:1.00

             From January 31, 2001 through
             and including February 27, 2001         1.90:1.00

             Thereafter                              2.00:1.00

Notwithstanding anything to the contrary contained above in this Section 9.07,
at all times from and after the date upon which 90% of the Cookson Shares owned
by the Borrower on the Third Amendment Effective Date have been released
pursuant to Section 1 of the Third Amendment or have otherwise been sold or
disposed of, the Borrower shall not permit the Asset Coverage Ratio to be less
than 2.50:1.00."

            16. The definition of "Interim Period" appearing in Section 11.01 of
the Credit Agreement and Section 2 of the Second Amendment is hereby amended by
deleting the date "February 28, 2001" appearing therein and inserting the text
"the Third Amendment Effective Date" in lieu thereof.

            17. Section 11.01 of the Credit Agreement is hereby amended by
inserting therein the following new definitions in the appropriate alphabetical
order:

            "Aggregate Put Number" shall mean, with respect to each Cookson
Derivative Transaction, the number of Available Cookson Shares subject to the
Put Option entered into with respect thereto, which number must be consistent
with the requirements of clause (ii) of the definition of Cookson Derivative
Transaction contained herein.

            "Aggregate Put Strike Price" shall mean, with respect to any
Available Cookson Shares the subject of any Cookson Derivative Transaction, the
per share Put Strike Price applicable to such Available Cookson Shares
multiplied by the number of Available Cookson Shares (in no event to exceed the
number of Available Cookson Shares actually released in connection with the
respective Cookson Derivative Transaction) subject to such Cookson Derivative
Transaction.


                                      -10-
<PAGE>

            "Available Cookson Shares" shall mean, at any time, all or any
portion of the Cookson Shares owned by the Borrower on the Third Amendment
Effective Date (and any Cookson Shares thereafter issued in substitution
therefor, or as dividends, distributions or rights issues with respect to such
Cookson Shares) less the amount of Cookson Shares thereafter sold, transferred
or disposed of by the Borrower other than in connection with one or more Cookson
Derivative Transactions.

            "Cookson Confirmation" shall mean, with respect to each Cookson
Derivative Transaction, the related Confirmation pursuant to, and as defined in,
the Master Option Agreement, which confirmation in any event shall include a
written confirmation from Deutsche setting forth the details (including without
limitation the number of shares sold short in the respective Cookson Derivative
Transaction, the Aggregate Put Number for the respective Cookson Derivative
Transaction, the Put Strike Price and Aggregate Put Strike Price for the
respective Cookson Derivative Transaction and a description of any Call Options
entered into as part of the respective Cookson Derivative Transaction) of the
respective Cookson Derivative Transaction.

            "Cookson Derivative Transaction" shall mean, (i) the short sale (at
fair market value as reasonably determined by Deutsche) of any number of
Available Cookson Shares so long as such number is consistent with the
requirements of Section 1(b)(i) of the Third Amendment, during a given Cookson
Derivative Transaction Period, (ii) the entering into by the Borrower and
Deutsche, in accordance with the Cookson Derivative Transaction Documents, of a
Put Option with respect to a number of Cookson Shares equal to the number of
Available Cookson Shares sold short during the respective Cookson Derivative
Transaction Period as contemplated by preceding clause (i) multiplied by the
Relevant Multiplier, whereby the Borrower will have the right to put such number
of Cookson Shares to Deutsche on the applicable Valuation Date at the Put Strike
Price, (iii) in connection with such Put Option, the entering into by the
Borrower of a Call Option entitling Deutsche to purchase from the Borrower the
same number of Cookson Shares as is subject to the respective Put Option as
described in preceding clause (ii) at a price which is not less than the Value
of such Cookson Shares on the date of the respective Cookson Confirmation and
(iv) following the occurrence of the transactions described in preceding clauses
(i) through (iii), the incurrence by the Borrower of Cookson Facility Loans in
the principal amount contemplated by Section 1(a)(ii) of the Third Amendment.

            "Cookson Derivative Transaction Documents" shall mean the Master
Option Agreement, the Cookson Facility, any note issued pursuant thereto, any
other credit arrangements entered into in connection with the Master Option
Agreement, the Pledge and Security Annex (as defined in the Master Option
Agreement), any account control agreement related thereto and all Cookson
Confirmations, in each case as same may be from time to time in effect.

            "Cookson Derivative Transaction Period" shall mean, with respect to
each Cookson Derivative Transaction, the weekly period (beginning on a Monday
and ending on a Friday) during which one or more short sales of Available
Cookson Shares occurs, in each case so long as Cookson Facility Loans relating
thereto are incurred during the immediately succeeding week.


                                      -11-
<PAGE>

            "Cookson Facility" shall mean the Credit Annex, dated as of January
26, 2001 among the Borrower and Deutsche, as same may be amended, modified or
supplemented from time to time.

            "Cookson Facility Loan" shall mean all "Loans" under, and as defined
in, the Cookson Facility, all of which Cookson Facility Loans shall be incurred
(and denominated) in Pounds Sterling.

            "Deutsche" shall mean Deutsche Bank AG, London Branch, Deutsche Bank
AG, New York Branch or Deutsche Banc Alex. Brown, Inc.

            "Dollar Equivalent" of an amount denominated in Pounds Sterling
shall mean, at any time for the determination thereof, the amount of Dollars
which could be purchased with the amount of Pounds Sterling involved in such
computation at the spot exchange rate therefor as quoted by the Administrative
Agent as of 11:00 a.m. (London time) on the date of any determination thereof
for purchase on such date.

            "Master Option Agreement" shall mean the Master Option Agreement,
dated as of January 26, 2001 between Deutsche and the Borrower, as counterparty,
as amended, modified or supplemented from time to time.

            "Pounds Sterling" shall mean lawful currency of Great Britain
denominated in pounds sterling.

            "Put Strike Price" shall mean, for any definitive Cookson Derivative
Transaction, the per share Put Strike Price set forth in the applicable Cookson
Confirmation which shall be no less than 85% of the weighted average price of
Available Cookson Shares sold short by Deutsche (which short sales must be at
fair market value as reasonably determined from time to time by Deutsche) during
the respective Cookson Derivative Transaction Period.

            "Relevant Multiplier" shall mean, with respect to each Cookson
Derivative Transaction, a multiplier established by Deutsche at the beginning of
the respective Cookson Derivative Transaction Period, which multiplier shall
apply for the respective Cookson Derivative Transaction Period and must be a
number not less than 1.0 and not greater than 1.5.

            "Third Amendment" shall mean the Third Amendment to Credit Agreement
and Second Amendment to US Pledge Agreement, dated as of January 26, 2001.

            "Third Amendment Effective Date" shall mean the Third Amendment
Effective Date under, and as defined in, the Third Amendment.

            18. Section 7 of the US Pledge Agreement is hereby amended by (i)
deleting the second sentence of the introductory paragraph of such Section 7 in
its entirety and (ii) deleting the text "Subject to the immediately preceding
sentence, in the case of clauses (i) and (ii) below, the" appearing at the
beginning of the third sentence of the introductory paragraph of such Section 7
and inserting the text "The" in lieu thereof.


                                      -12-
<PAGE>

            19. The Lenders and the Borrower hereby agree that (i) from and
after the date upon which 90% of the Cookson Shares owned by the Borrower on the
Third Amendment Effective Date have been released from the security interests
created pursuant to the UK Pledge Agreement (and/or the other relevant Credit
Documents) as contemplated by Section 1 of this Amendment or have otherwise been
sold or disposed pursuant to Section 9.06(a) of the Credit Agreement, each
reference to the ratio "2.00:1.00" appearing in Section 16 of the US Pledge
Agreement shall be deleted and the reference "2.50:1.00" shall be inserted in
lieu thereof and (ii) if at such time the Borrower is not in compliance with the
provisions of such Section 16 of the US Pledge Agreement, the Borrower shall
immediately take actions necessary to comply with such Section as modified
pursuant to this Section 19.

            20. In order to induce the Lenders to enter into this Amendment, the
Borrower hereby represents and warrants that (i) the representations, warranties
and agreements contained in Section 7 of the Credit Agreement are true and
correct in all material respects on and as of the date hereof, both before and
after giving effect to this Amendment (except with respect to any
representations and warranties limited by their terms to a specific date hereof,
which shall be true and correct in all material respects as of such date) and
(ii) there exists no Default or Event of Default on and as of the date hereof,
both before and after giving effect to this Amendment.

            21. This Amendment is limited as specified and shall not constitute
a modification, acceptance or waiver of any other provision of the Credit
Agreement or other Credit Document.

            22. This Amendment may be executed in any number of counterparts and
by the different parties hereto on separate counterparts, each of which
counterparts when executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument. A complete set of
counterparts shall be lodged with the Borrower and the Administrative Agent.

            23. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE
STATE OF NEW YORK.

            24. This Amendment shall become effective on the date (the "Third
Amendment Effective Date") when (i) the Borrower and the Supermajority Lenders
shall have signed a counterpart hereof (whether the same or different
counterparts) and shall have delivered (including by way of facsimile) the same
to the Administrative Agent at the Notice Office, (ii) each Deutsche signatory
listed on the attached Acknowledgment and Agreement shall have signed a
counterpart hereof (whether the same or different counterparts) and shall have
delivered (including by way of facsimile) the same to the Administrative Agent
at the Notice Office and (iii) the Administrative Agent shall have received from
Proskauer Rose LLP, counsel to the Borrower, an opinion addressed to the
Administrative Agent, the Syndication Agent, the Documentation Agent and each of
the Lenders, and dated the Third Amendment Effective Date, which opinion shall
be in form and substance satisfactory to the Administrative Agent, and cover
such matters incident to this Amendment and the transactions contemplated herein
and as the


                                      -13-
<PAGE>

Administrative Agent may reasonably request (including, but not limited to, the
compliance by the Borrower with Regulation U).

            25. Upon the occurrence of the Third Amendment Effective Date, the
Credit Agreement and the US Pledge Agreement shall be amended as set forth
herein.

            26. From and after the Third Amendment Effective Date, all
references in the Credit Agreement and the other Credit Documents to the Credit
Agreement and the US Pledge Agreement shall be deemed to be references to the
Credit Agreement and the US Pledge Agreement as modified hereby.

            27. Each of the parties hereto hereby acknowledge and agree that
only the provisions of Section 1 (and the related defined terms) shall inure to
the benefit of Deutsche (so long as Deutsche complies with its obligations set
forth in said Section 1).

            28. Each of the parties hereto hereby acknowledges that Deutsche is
an affiliate of Bankers Trust Company.

                                      * * *


                                      -14-
<PAGE>

            IN WITNESS WHEREOF, the parties hereto have caused their duly
authorized officers to execute and deliver this Amendment as of the date first
above written.

                                        THE ALPINE GROUP, INC.

                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:

                                        BANKERS TRUST COMPANY,
                                        Individually and as Administrative Agent

                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:

                                        FLEET NATIONAL BANK, Individually and as
                                        Syndication Agent

                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:

                                        BANK OF AMERICA, N.A.,
                                        Individually and as Documentation Agent

                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:


                                      -15-
<PAGE>

                                             THE BANK OF NOVA SCOTIA

                                          By:
                                             -----------------------------------
                                             Name:
                                             Title:


                                      -16-
<PAGE>

ACKNOWLEDGEMENT AND AGREEMENT

            Each of undersigned hereby agrees for the benefit of the Lenders to
be bound by the provisions applicable to Deutsche as set forth in Section 1 of
this Amendment, and further agrees that other than as expressly set forth in
such Section 1, the provisions of this Amendment shall not inure to the benefit
of Deutsche and the provisions set forth in such Section 1 shall only inure to
the benefit of Deutsche so long as it complies with its obligations under said
Section 1.

                                        DEUTSCHE BANK AG,
                                        LONDON BRANCH

                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:

                                        DEUTSCHE BANK AG,
                                        NEW YORK BRANCH

                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:

                                        DEUTSCHE BANC ALEX. BROWN, INC.

                                        By:
                                           -------------------------------------
                                           Name:
                                           Title:



<PAGE>

                                                                         ANNEX A

                          FORM OF OFFICER'S CERTIFICATE

            I, the undersigned, [Title of Authorized Officer] of THE ALPINE
GROUP, INC., a corporation organized and existing under the laws of the State of
Delaware (the "Borrower"), DO HEREBY CERTIFY that:

            1. This Certificate is being delivered pursuant to Section of
1(a)(vii) of the Third Amendment (the "Third Amendment") to Credit Agreement and
Second Amendment to US Pledge Agreement and Second Amendment and Acknowledgment,
dated as of January __, 2001, among the Borrower, the lenders from time to time
party thereto, Fleet National Bank (formerly known as Fleet Bank, N.A.), as
Syndication Agent, Bank of America, N.A., as Documentation Agent, Bankers Trust
Company, as Administrative Agent, Deutsche Bank AG, London Branch, Deutsche Bank
AG, New York Branch and Deutsche Banc Alex. Brown, Inc. Reference is hereby made
to the Credit Agreement dated as of November 23, 1999, among The Alpine Group,
Inc., various lenders from time to time party thereto, Fleet National Bank
(formerly known as Fleet Bank, N.A.), as Syndication Agent, Bank of America,
N.A., as Documentation Agent, and Bankers Trust Company, as Administrative
Agent, as amended, modified or supplemented from time to time (as so amended,
modified or supplemented from time to time, the "Credit Agreement"). Unless
otherwise defined herein, terms defined in the Credit Agreement or the Third
Amendment shall have the same meaning when used herein.

            2. The undersigned hereby requests the release from the UK Pledge
Agreement and other Credit Documents of _______ Cookson Shares, which number is
equal to the Aggregate Put Number of Cookson Shares in connection with the
respective Cookson Derivative Transaction and is the same as the number of
Cookson Shares subject to Put Options as specified in clause (i) of following
section numbered 3.

            3. With respect to the Available Cookson Shares being released on
the date hereof (such release hereinafter referred to as the "Release"), the
Borrower certifies that it has entered into, in accordance with the Cookson
Derivative Transaction Documents, (i) Put Options whereby the Borrower has the
right to put _______ Cookson Shares to Deutsche on _____ [Valuation Date for
such Put Options] at a Put Strike Price of _____ and (ii) Call Options, whereby
Deutsche is entitled to purchase such Available Cookson Shares at a price of not
less than the Value of such Available Cookson Shares on the date of the attached
Cookson Confirmation.

            4. Attached hereto is a true and correct copy of the Cookson
Confirmation dated _____, 20__ relating to Cookson Derivative Transactions
entered into between [name relevant Deutsche entity] and the Borrower.

            5. The Borrower hereby certifies that it has complied with all
conditions contained in Section 1 of the Third Amendment with respect to the
Release requested hereby.
<PAGE>

                                                                          Page 2

            6. Contemporaneously with the Release, the Borrower shall (x) incur
Cookson Facility Loans under the Cookson Facility in an aggregate principal
amount of (pound)___________, which is at least 85% of the Aggregate Put Strike
Price applicable to the Cookson Shares to be Released and is not in excess of
the Aggregate Put Strike Price applicable to the Cookson Shares to be Released
and (y) apply an amount equal to the Dollar Equivalent of the aggregate
principal amount of such Cookson Facility Loans to repay then outstanding Loans
as (and to the extent) required pursuant to Section 4.02(f) of the Credit
Agreement.

            7. Contemporaneously with the Release, the Total Commitment shall be
permanently reduced to the extent required pursuant to Section 3.03(b)(ii) of
the Credit Agreement.

            IN WITNESS WHEREOF, the undersigned has executed this Certificate as
of this ___ day of _________, 20__.

                                                 THE ALPINE GROUP, INC.

                                                 By:________________________
                                                      Name:
                                                      Title: