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                                                                   Exhibit 10.37

                   AMENDMENT AGREEMENT NO. 9 TO SECOND AMENDED

                          AND RESTATED CREDIT AGREEMENT

         This AMENDMENT AGREEMENT NO. 9 (this "Amendment"), dated as of
September 30, 2000, by and among SIGNAL TECHNOLOGY CORPORATION, a Delaware
corporation ("STC"), SIGNAL TECHNOLOGY SALES CORP., a United States Virgin
Islands corporation ("Sales" and, together with STC, the "Companies"), and FLEET
NATIONAL BANK, a national banking association formerly known as BankBoston, N.A.
and as The First National Bank of Boston (the "Bank"), amends the Second Amended
and Restated Credit Agreement dated as of September 30, 1993, as amended (as the
same may be further amended, modified, or supplemented from time to time the
"Credit Agreement"), by and among the Companies and the Bank. Capitalized terms
used but not defined herein shall have the meanings set forth for such terms in
the Credit Agreement.

         WHEREAS, the Companies have requested that the Bank agree to amend the
Credit Agreement; and

         WHEREAS, subject to the terms and provisions hereof, the Bank is
willing to do so;

         NOW, THEREFORE, the parties hereto hereby agree as follows:

Section 1. AMENDMENT TO CREDIT AGREEMENT. Subject to the satisfaction of the
conditions precedent set forth in Section 3 hereof, Section 1 of the Credit
Agreement is hereby amended by amending the definition of the term "Revolving
Credit Maturity Date" set forth therein to read as follows:

                  "REVOLVING CREDIT MATURITY DATE - December 31, 2000."


         Section 2. REPRESENTATIONS AND WARRANTIES. The Companies hereby
represent and warrant to the Bank as follows:

                  (a) REPRESENTATIONS AND WARRANTIES IN CREDIT AGREEMENT. The
         representations and warranties of the Companies contained in the Credit
         Agreement were true and correct in all material respects when made and
         continued to be true and correct in all material respects on the date
         hereof, except to the extent that compliance with such representations
         and warranties has previously been waived in writing by the Bank or
         such representations and warranties relate expressly to an earlier
         date.



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                  (b) AUTHORITY, NO CONFLICTS, ENFORCEABILITY OF OBLIGATIONS,
         ETC. Each of the Companies hereby confirms that the representations and
         warranties of the Companies contained in Sections 8.1 and 8.3 of the
         Credit Agreement are true and correct on and as of the date hereof as
         if made on the date hereof, treating this Amendment, the Credit
         Agreement as amended hereby, and the other Loan Documents as amended
         hereby, as "Loan Documents" for the purposes of making said
         representations and warranties.

         Section 3. CONDITIONS TO EFFECTIVENESS. The effectiveness of this
Amendment shall be subject to the delivery to the Bank by (or on behalf of) each
of the Companies, as the case may be, contemporaneously with the execution
hereof, of the following, in form and substance satisfactory to the Bank:

                  (a) this Amendment signed by each of the Companies and the
         Bank; and

                  (b) any other confirmatory or corporate authority document or
         instrument the Bank may reasonably request.

         Section 4. MISCELLANEOUS PROVISIONS. Except as otherwise expressly
provided by this Amendment, all of the terms, conditions and provisions of the
Credit Agreement and the other Loan Documents shall remain in full force and
effect. Each of the Companies confirms and agrees that the joint and several
Obligations of the Companies to the Bank, as amended and supplemented hereby,
are entitled to the benefits of the Loan Documents. The parties hereto hereby
acknowledge and agree that all references to the Credit Agreement and the
Obligations thereunder contained in any of the Loan Documents shall be
references to the Credit Agreement and the Obligations as amended hereby and as
the same may be amended, modified, supplemented, or restated from time to time.
This Amendment may be executed in any number of counterparts, but all such
counterparts shall together constitute but one instrument. In making proof of
this Amendment it shall not be necessary to produce or account for more than one
counterpart signed by each party hereto by and against which enforcement hereof
is sought. The Companies hereby jointly and severally confirm their obligations
to pay promptly upon request all reasonable out-of-pocket costs and expenses
incurred or sustained by the Bank in connection with this Amendment, including
the reasonable fees and expenses of Sullivan & Worcester LLP.

         Section 5. GOVERNING LAW. This Amendment shall be construed according
to and governed by the internal laws of The Commonwealth of Massachusetts
without reference to principles of conflicts of law.

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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their respective officers thereunto duly authorized.

                                  SIGNAL TECHNOLOGY CORPORATION


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

                                  SIGNAL TECHNOLOGY SALES CORP.


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

                                  FLEET NATIONAL BANK


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