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MICRODYNE CORPORATION                            1997 ANNUAL REPORT ON FORM 10-K
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                                                                   Exhibit 10.35

                               FIFTH AMENDMENT TO
                                CREDIT AGREEMENT

         THIS FIFTH AMENDMENT TO CREDIT AGREEMENT (the "Amendment"), dated and
effective as of March 14, 1997, is made by and between MICRODYNE CORPORATION, a
Maryland corporation (the "Borrower"), CRESTAR BANK and NBD BANK (the "Banks"),
and CRESTAR BANK ("Crestar") as agent (the "Agent") for the Banks.

                                    RECITALS

         The Borrower, the Banks and the Agent are parties to a Credit
Agreement, dated as of January 27, 1995, as amended by the First Amendment to
Credit Agreement, dated as of October 26, 1995, the Second Amendment to Credit
Agreement, dated as of June 30, 1996, the Third Amendment to Credit Agreement,
dated as of August 19, 1996, and the Fourth Amendment to Credit Agreement dated
as of September 27, 1996 (as further amended, modified or supplemented from time
to time, the "Agreement"). Terms defined in the Agreement shall have the same
defined meanings when such terms are used in this Amendment.

         The Borrower, the Agent and the Banks have agreed to amend certain
provisions of the Agreement. Accordingly, for valuable consideration, the
receipt and sufficiency of which are acknowledged, the Borrower, the Banks and
the Agent agree as follows:

         11..  The Applicable DC Advance Percentage shall be 0% and Eligible
Data Communications Receivables shall not be included in the Borrowing Base
unless the Banks elect, in their sole discretion, to increase the Applicable DC
Advance Percentage at some subsequent date. The Banks will reconsider the
Borrower's request to reestablish the Applicable DC Advance Percentage after the
Banks review the Borrower's financial statements for its fiscal quarter ending
on June 29, 1997.

         22.   Eligible Inventory shall not include at any time more than
$250,000 of finished goods completed under a Telemetry Division contract and for
which payment is not yet due from a Customer.

         33.   Section 7.3 shall be amended to read in its entirety as follows:

               "SECTION 7.3 Financial Covenants. So long as any Note shall
         remain unpaid, any Letter of Credit shall remain outstanding or any
         Bank shall have any Commitment hereunder, the Borrower shall maintain,
         unless the Banks shall otherwise consent in writing:

                    (a)     Net Income. For the fiscal quarter ending on June
         29, 1997, and each subsequent fiscal quarter, Net Income of greater
         than $1.

                    (b)     Tangible Net Worth. As of the end of each fiscal
         quarter of the Borrower, beginning on June 29, 1997, Tangible Net Worth
         of not less than the Tangible Net Worth reflected in the Borrower's
         financial statements for the fiscal quarter ending March 30, 1997."

         44.   Except for the amendments to the Agreement expressly set forth
above, the Agreement and the other Loan Documents shall remain in full force and
effect. The Borrower acknowledges and agrees that this Amendment only amends the
terms of the Agreement and is not a novation, and the Borrower ratifies and
confirms the remaining terms and provisions of the Agreement and the other Loan
Documents in all respects. Nothing in this Amendment shall require the Banks to
grant any further amendments to the terms of the Loan Documents. The failure of
the Borrower to perform or observe any covenant or agreement contained herein
shall constitute an Event of Default under the Credit Agreement.


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MICRODYNE CORPORATION                            1997 ANNUAL REPORT ON FORM 10-K
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         55.   The Borrower acknowledges and agrees that (a) there are no
defenses, counterclaims or setoffs against any of its obligations under the Loan
Documents, and (b) the prior grant of a security interest in the Collateral
created by the Security Agreement and the Patent and Trademark Assignment
continues to secure the Obligations, is in full force and effect, and is
ratified and confirmed by the Borrower in all respects.

         66.   The Borrower represents and warrants that this Amendment has been
duly authorized, executed and delivered by it in accordance with resolutions
adopted by its board of directors. All other representations and warranties made
by the Borrower in the Loan Documents are incorporated by reference in this
Amendment and are deemed to have been repeated as of the date of this Amendment
with the same force and effect as if set forth in this Amendment, except that
any representation or warranty relating to any financial statements shall be
deemed to be applicable to the financial statements most recently delivered to
the Banks in accordance with the provisions of the Loan Documents.

         77.   The Borrower agrees to pay all costs and expenses incurred by the
Agent and the Banks in connection with this Amendment, including, but not
limited to, reasonable attorneys' fees.

         88.   This Amendment shall be governed by the laws of the Commonwealth
of Virginia, without reference to conflict of laws principles.

         99.   This Amendment may be executed by the parties individually or in
any combination, in one or more counterparts, each of which shall be an original
and all of which together constitute one and the same instrument.

                         [SIGNATURES ON FOLLOWING PAGE]

         WITNESS the following signatures.

                             BORROWER:

                             MICRODYNE CORPORATION,
                             a Maryland corporation
                             By: /s/ Christian J. Spitz
                             Name: Christian J. Spitz
                             Title: Senior Vice President and CFO

                             AGENT:

                             CRESTAR BANK
                             By:  /s/ Miriam M. Sadler
                                      Miriam M. Sadler
                                      Senior Vice President

                             BANKS:

                             CRESTAR BANK
                             By:  /s/ Miriam M. Sadler
                                      Miriam M. Sadler
                                      Senior Vice President

                             NBD BANK

                             By: /s/Robert J. Hill
                             Name:  Robert J. Hill
                             Title: First Vice-President


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