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                         L-3 COMMUNICATIONS CORPORATION

                       CONSENT, WAIVER AND FIRST AMENDMENT
                         TO NEW 364 DAY CREDIT AGREEMENT

     This CONSENT, WAIVER AND FIRST AMENDMENT TO THE NEW 364 DAY CREDIT
AGREEMENT (this "AMENDMENT") is dated as of April 28, 2000 and entered into by
and among L-3 COMMUNICATIONS CORPORATION, a Delaware corporation (the
"BORROWER") which is wholly owned by L-3 COMMUNICATIONS HOLDINGS, INC., a
Delaware corporation ("HOLDINGS"), the Lenders party to the Credit Agreement
referred to below on the date hereof (the "LENDERS"), BANK OF AMERICA, N.A.,
("BOA"), as administrative agent for the Agents (as defined below) and the
Lenders (in such capacity, the "ADMINISTRATIVE AGENT") and certain financial
institutions named as co-agents, LEHMAN COMMERCIAL PAPER INC. ("LCPI") as
syndication agent and documentation agent (in such capacity, the "SYNDICATION
AGENT" and the "DOCUMENTATION AGENT"). All capitalized terms used herein without
definition shall have the same meanings herein as set forth in the Credit
Agreement (as defined below).

                              W I T N E S S E T H:

     WHEREAS, the Borrower, the Lenders, the Syndication Agent, the
Documentation Agent, the Administrative Agent and certain other parties have
entered into the New 364 Day Credit Agreement dated as of April 24, 2000 (as
amended, supplemented, restated or otherwise modified from time to time, the
"CREDIT AGREEMENT"); and

     WHEREAS, the Borrower desires that the Lenders consent to a waiver and
amendment of certain provisions of the Credit Agreement and related Credit
Documents to, inter alia, (i) allow Borrower to capitalize a new Subsidiary by
contributing the assets and delegating the liabilities of the Acquired Company
to such new Subsidiary (the "TCAS Subsidiary"), (ii) exempt the TCAS Subsidiary
from becoming a party to a Subsidiary Guarantee or Subsidiary Pledge Agreement
so long as it is not a Wholly Owned Subsidiary, (iii) permit the issuance by
Holdings and the guarantee by Borrower of Permitted Convertible Securities and
(iv) make certain other amendments to the Credit Agreement.

     NOW, THEREFORE, in consideration of the premises and the agreements,
provisions and covenants herein contained, the parties hereto agree as follows:

     SECTION 1. LIMITED CONSENTS AND WAIVERS.

     1.1 Permitted Convertible Securities. Subject to the satisfaction of each
of the conditions to effectiveness set forth in Section 6 of this Amendment, the
Requisite Class Lenders hereby consent to an amendment to the Parent Guarantee
to permit Holdings to issue the Permitted Convertible Securities.

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     1.2 TCAS Contribution. Subject to the satisfaction of each of the
conditions to effectiveness set forth in Section 7 of this Amendment, the
Required Lenders hereby consent to the contribution and delegation by Borrower
of all of the assets and liabilities related to the Acquired Company (the "TCAS
CONTRIBUTION") to a new Subsidiary of Borrower (the "TCAS SUBSIDIARY") and,
solely for the purposes of permitting such TCAS Contribution, waive compliance
with the provisions of Subsection 7.6 and 7.9 of the Credit Agreement which
would otherwise limit such a contribution.

     SECTION 2. GENERAL AMENDMENTS. Subject to the satisfaction of each of the
conditions to effectiveness set forth in Section 5 of this Amendment, the
Borrower and the Required Lenders hereby agree to amend the Credit Agreement as
follows:

     2.1 Subsection 1.1 of the Credit Agreement is hereby amended to add the
following new defined terms in alphabetical order:

         "Convertible Securities": at any time, (i) unsecured convertible debt
     securities issued by Holdings having no principal amortization or sinking
     fund requirements which are guaranteed by Borrower but subordinated in
     right of payment to the Obligations and the "Obligations" as defined under
     the Facility A Credit Agreement and the Facility B Credit Agreement on
     terms and conditions acceptable to the Agents and/or (ii) unsecured debt
     securities issued by Holdings to a trust (the "Trust") having no principal
     amortization or sinking fund requirements which are guaranteed by Borrower
     but subordinated in right of payment to the Obligations and the
     "Obligations" as defined under the Facility A Credit Agreement and the
     Facility B Credit Agreement on terms and conditions acceptable to the
     Agents which Trust, in turn, issues preferred stock securities to investors
     which are convertible at the option of the holder thereof into shares of
     common stock of Holdings.

         "Required Class Lenders": at any time, (a) for the Lenders having Loan
     Exposure, Lenders having or holding more than 50% of the aggregate Loan
     Exposure of all Lenders, (b) for the Facility A Lenders having Facility A
     Loan Exposure, Facility A Lenders having or holding more than 50% of the
     aggregate Facility A Loan Exposure of all Facility A Lenders and (c) for
     the Facility B Lenders having Facility B Loan Exposure, Facility B Lenders
     having or holding more than 50% of the aggregate Facility B Loan Exposure
     of all Facility B Lenders.

         "TCAS Subsidiary": a Subsidiary of Borrower organized as a Delaware
     limited liability company which will hold and operate the assets and
     business of the Acquired Company.

         "Wholly Owned Subsidiary": a Subsidiary of Borrower, the Capital Stock
     of which is 100% owned and controlled, directly or indirectly, by Borrower.

     2.2 Subsections 2.6(b)(i), (ii), (iii) and (iv) of the Credit Agreement are
hereby amended and restated in their entirety to read as follows:


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         (i) If, subsequent to the Closing Date, Holdings or any of its
     Subsidiaries shall incur or permit the incurrence of any Indebtedness
     (other than Indebtedness permitted pursuant to subsection 7.2(a) through
     and including subsection 7.2(k)), 100% of the Net Proceeds thereof shall be
     promptly ratably applied toward the prepayment of the Loans, the Facility A
     Loans and the Facility B Loans and, unless the Required Class Lenders shall
     have waived such requirement in writing, on or before the 60th day
     following the date of receipt of such Net Proceeds (such 60 day period,
     herein, the "Debt Prepayment Waiting Period"), the Commitments, the
     Facility A Commitments and the Facility B Commitments shall be permanently
     reduced as set forth in clause (iv) of this subsection 2.6(b) by the amount
     so prepaid on the last day of the Debt Prepayment Waiting Period. During
     the term of any Debt Prepayment Waiting Period, a portion of the
     Commitments, the Facility A Commitments and the Facility B Commitments
     equal to the amount of prepayments received in respect of the Loans, the
     Facility A Loans and the Facility B Loans, as applicable, from the issuance
     and/or incurrence of such Indebtedness shall be unavailable to Borrower and
     deemed excluded from each Lender's, Facility A Lender's and Facility B
     Lender's "Available Commitment" (as such term is defined herein and in each
     of the Facility A Credit Agreement and Facility B Credit Agreement) unless
     Borrower shall have received a written waiver of such mandatory commitment
     reduction from the Required Class Lenders. Nothing in this paragraph (b)
     shall be deemed to permit any Indebtedness not permitted by subsection 7.2.

         (ii) If, subsequent to the Original Closing Date, Holdings or any of
     its Subsidiaries shall receive Net Proceeds from any Asset Sale (other than
     in respect of a sale of all of the Capital Stock of the TCAS Subsidiary
     owned, directly or indirectly, by Borrower (a "Final TCAS Sale")), such Net
     Proceeds, subject to the Applicable Holdback (defined below) shall be
     promptly and ratably applied toward the prepayment of the Loans, the
     Facility A Loans and the Facility B Loans and permanent reduction of the
     Commitments, the Facility A Commitments and the Facility B Commitments as
     set forth in clause (iv) of this subsection 2.6(b); provided that Net
     Proceeds from any Asset Sales (other than in respect of a Final TCAS Sale)
     shall not be required to be so applied to the extent that such Net Proceeds
     are used by the Borrower or such Subsidiary to acquire assets to be
     employed in the business of the Borrower or its Subsidiaries within 365
     days of receipt thereof, but if such Net Proceeds, subject to the
     Applicable Holdback (as defined below), are not so used, 100% of the amount
     of such Net Proceeds not so used shall be applied toward the prepayment of
     the Loans and the permanent reduction of the Commitments as set forth in
     clause (iv) of this subsection

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     2.6(b) on the earlier of (x) the 366th day after receipt of such Net
     Proceeds and (y) the date on which the Borrower has determined that such
     Net Proceeds shall not be so used. If Holdings, Borrower or any of its
     Subsidiaries shall receive Net Proceeds from a Final TCAS Sale, such Net
     Proceeds shall be applied on or prior to the third Business Day after
     receipt thereof toward prepayment of the Loans, the Facility A Loans and
     the Facility B Loans and, unless the Required Class Lenders shall have
     waived such requirement in writing, on or before the 60th day following the
     date of such Final TCAS Sale (such 60 day period, herein, the "TCAS Waiting
     Period"), the Commitments, the Facility A Commitments and the Facility B
     Commitments shall be permanently reduced as set forth in clause (iv) of
     this subsection 2.6(b) by the amount so prepaid on the last day of the TCAS
     Waiting Period. During the term of any TCAS Waiting Period, a portion of
     the Commitments, the Facility A Commitments and the Facility B Commitments
     equal to the amount of prepayments received in respect of the Loans, the
     Facility A Loans and the Facility B Loans from such Final TCAS Sale shall
     be unavailable to Borrower and deemed excluded from each Lender's, Facility
     A Lender's and Facility B Lender's "Available Commitment" (as such term is
     defined herein and in each of the Facility A Credit Agreement and Facility
     B Credit Agreement) unless Borrower shall have received a written waiver of
     such mandatory commitment reduction from the Required Class Lenders. As
     used herein, "Applicable Holdback" shall mean an amount of Net Proceeds not
     in excess of $20,000,000 derived from any Asset Sales (other than a Final
     TCAS Sale) occurring since the Original Closing Date that has not been
     applied toward the prepayment of Loans and the permanent reduction of the
     Commitments as set forth in clause (iv) of subsection 2.6(b) which Borrower
     and/or its applicable Subsidiary may retain and not apply as a mandatory
     prepayment without the requirement of utilizing the same to acquire assets
     to be employed in the business of the Borrower or such applicable
     Subsidiary; provided, that if any Event of Default shall have occurred and
     be continuing, the Applicable Holdback amount shall be automatically
     reduced to zero unless and until such Event of Default is acknowledged in
     writing by the Required Lenders (or all the Lenders in cases where the
     unanimous consent of the Lenders is required) as cured or waived.

         (iii) If, subsequent to the Closing Date, any Capital Stock (other than
     any Convertible Securities which shall for all purposes under this
     Agreement be deemed Indebtedness for borrowed money) shall be issued by
     Holdings, the Borrower or any of its Subsidiaries, an amount equal to 50%
     of the Net Proceeds thereof shall be promptly ratably applied toward the
     prepayment of the Loans on the date of issuance and, unless the Required
     Lenders shall have waived such requirement in writing, on or before the
     60th day following the date of receipt of such Net Proceeds (such 60 day
     period, herein, the "Equity Issuance Waiting Period"), the Commitments
     shall be permanently reduced as set forth in clause (iv) of this subsection
     2.6(b) by the amount so prepaid on the last day of the Equity Issuance
     Waiting Period. During the term of any Equity Issuance Waiting Period, a
     portion of the Commitments equal to the amount of prepayments received in
     respect of the Loans from the issuance of such Capital Stock shall be
     unavailable to Borrower for Loans and deemed excluded from each Lender's
     Available Commitment unless Borrower shall have received a written waiver
     of such mandatory commitment reduction from the Required Lenders. Nothing
     in this paragraph (b) shall be deemed to permit any issuance of Capital
     Stock not permitted by subsection 7.6.

         (iv) Except during any period in which an Event of Default has occurred
     and is continuing, any mandatory prepayments required by subsection
     2.6(b)(i) and (ii) shall be applied ratably to the outstanding principal
     amount of Facility A Loans, Facility B Loans and Loans, with a
     corresponding ratable permanent reduction of the Facility A Commitments,
     the Facility B Commitments and the Commitments as and when required by
     subsection 2.6(b)(i) and (ii). Commitment, Facility A Commitment and
     Facility B Commitment reductions made pursuant to subsections 2.6(b)(i) and
     (ii) (and

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     the corresponding subsections of the Facility A Credit Agreement and the
     Facility B Credit Agreement) hereof shall be applied to each Lender's
     respective Commitment, each Facility A Lender's Facility A Commitment
     and/or each Facility B Lender's Facility B Commitment, as applicable, on a
     pro rata basis and shall reduce permanently such Commitments, Facility A
     Commitments and Facility B Commitments. In addition, except during any
     period in which an Event of Default has occurred and is continuing, any
     mandatory prepayments required by subsection 2.6(b)(iii) shall be applied
     ratably to the outstanding principal amount of Loans, with a corresponding
     permanent reduction of the Commitments as and when required by subsection
     2.6(b)(iii). The Commitment reductions made pursuant to subsection
     2.6(b)(iii) hereof shall be applied to each Lender's respective Commitment
     and shall reduce permanently such Commitments. At any time that an Event of
     Default has occurred and is continuing, all mandatory prepayments shall be
     applied in accordance with the terms of subsection 2.12 hereof (and the
     corresponding subsection of the Facility A Credit Agreement and the
     Facility B Credit Agreement). Mandatory prepayments shall not be subject to
     any minimum amount requirement.

     2.3 Subsection 7.2(d) of the Credit Agreement is hereby amended and
restated in its entirety to read as follows:

         (d) additional Indebtedness of the Borrower and its Subsidiaries not
     exceeding $50,000,000 in aggregate principal amount at any one time
     outstanding (of which up to $35,000,000 may be secured by Liens permitted
     pursuant to subsection 7.3(i) hereof);

     2.4 Subsection 9.5 of the Credit Agreement is hereby amended by (i)
deleting the term "Required Lenders" appearing therein and inserting the term
"Required Class Lenders" in place thereof and (ii) adding the language ", the
Facility A Lenders and the Facility B Lenders taken as a whole" immediately
prior to the period "." appearing at the end thereof.

     SECTION 3. AMENDMENTS GENERALLY RELATING TO PERMITTED CONVERTIBLE
SECURITIES. Subject to the satisfaction of each of the conditions to
effectiveness set forth in Section 6 of this Amendment, the Borrower and the
Requisite Class Lenders hereby agree to amend the Credit Agreement as follows:

     3.1 The definition of "Permitted Stock Payments" in subsection 1.1 of the
Credit Agreement is hereby amended and restated in its entirety to read as
follows:

         "Permitted Stock Payments": (A) dividends by Borrower to Holdings in
     amounts equal to the amounts required for Holdings to (i) pay franchise
     taxes and other fees required to maintain its legal existence and (ii)
     provide for other operating costs of up to $1,000,000 per fiscal year, (B)
     dividends by Borrower to Holdings in amounts equal to amounts required for
     Holdings to pay federal, state and local income taxes to the extent such
     income taxes are actually due and owing, provided that the aggregate amount
     paid under this clause (B) does not exceed the amount that Borrower would
     be required to pay in respect of the income of Borrower and its
     Subsidiaries if Borrower were a stand alone entity that was not owned by
     Holdings, (C) from and after May 1, 1999, dividends by

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     Borrower to Holdings payable solely out of Excess Cash Flow, provided that,
     with respect to this clause (C), (i) as of the last day of the most
     recently completed fiscal quarter the Debt Ratio is less than or equal to
     3.5 to 1, and (ii) the aggregate amount of dividends paid by Borrower to
     Holdings under this clause (C) since the Original Closing Date does not
     exceed $5,000,000 and (D) dividends by Borrower to Holdings to fund
     interest expense in respect of the Permitted Convertible Securities issued
     by Holdings, provided that such dividends under this clause (D) shall not,
     in any fiscal year, exceed an amount equal to the interest actually
     accruing on the outstanding principal amount of such Permitted Convertible
     Securities in such fiscal year less the sum of all intercompany advances
     funded pursuant to subsection 7.9(l) hereof by Borrower to Holdings in
     respect of such Permitted Convertible Securities in such fiscal year.

     3.2 Subsection 1.1 of the Credit Agreement is hereby further amended to add
the following new defined terms in alphabetical order:

         "Permitted Convertible Securities": as defined in subsection 7.4(h).

 3.3 Subsection 7.4 of the Credit Agreement is hereby amended by (i) deleting
the period "." appearing at the end of subsection 7.4(g) and inserting the
language "; and" in place thereof and (ii) adding the following new subsection
7.4(h) at the end thereof:

         (h) Guarantee Obligations in respect of up to $400,000,000 principal
     amount of Convertible Securities issued by Holdings having an annual
     interest rate not in excess of 7% per annum (the "Permitted Convertible
     Securities").

     3.4 Subsection 7.9 of the Credit Agreement is hereby amended by (i)
deleting the word "and" at the end of subsection 7.9(j), (ii) deleting the
period "." at the end of subsection 7.9(k) and inserting the language "; and" in
place thereof and (iii) adding the following new subsection 7.9(l) at the end
thereof:

         (l) Investments consisting of intercompany advances by Borrower to
     Holdings to fund interest expense in respect of the Permitted Convertible
     Securities issued by Holdings, provided that such intercompany advances
     shall not, in any fiscal year, exceed an amount equal to the interest
     actually accruing on the outstanding principal amount of such Permitted
     Convertible Securities in such fiscal year less the sum of all Permitted
     Stock Payments funded pursuant to clause (D) of the definition thereof by
     Borrower to Holdings in respect of such Permitted Convertible Securities in
     such fiscal year.

     SECTION 4. AMENDMENTS GENERALLY RELATING TO THE TCAS SUBSIDIARY. Subject to
the satisfaction of each of the conditions to effectiveness set forth in Section
7 of this Amendment, the Borrower and the Required Lenders hereby agree to amend
the Credit Agreement as follows

     4.1 Section 1 of the Credit Agreement is hereby amended by adding the
following new Subsection 1.3:

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         1.3 Accounting for Interests in TCAS Subsidiary. Notwithstanding
     anything to the contrary contained in this Agreement or any other Credit
     Document, for purposes of computing the amount of any financial terms
     and/or computing compliance with any of the financial tests and/or
     covenants set forth in this Agreement or any other Credit Document in
     respect of the TCAS Subsidiary at any time it is not a Wholly Owned
     Subsidiary, Borrower shall (i) only be permitted to include that portion of
     any assets and/or liabilities attributable to the TCAS Subsidiary which
     corresponds directly with the percentage of Capital Stock of the TCAS
     Subsidiary owned, directly or indirectly, by Borrower and (ii) eliminate
     depreciation and amortization expenses of the TCAS Subsidiary included in
     the consolidated financial statements of the Borrower that are applicable
     to the minority interests owned by Persons other than Borrower or its
     Subsidiaries in the TCAS Subsidiary in determining Borrower's Consolidated
     EBITDA.

     4.2 Subsection 6.10(b) of the Credit Agreement is hereby amended and
restated in its entirety to read as follows:

         (b) With respect to any Person that, subsequent to the Original Closing
     Date, becomes a direct or indirect Subsidiary of the Borrower, promptly
     (and in any event within 30 days after such Person becomes a Subsidiary):
     (i) cause such new Subsidiary to become a party to the Subsidiary Pledge
     Agreement and the Subsidiary Guarantee and (ii) if requested by the
     Administrative Agent or the Required Lenders, deliver to the Administrative
     Agent legal opinions relating to the matters described in clause (i)
     immediately preceding, which opinions shall be in form and substance, and
     from counsel, reasonably satisfactory to the Administrative Agent.
     Notwithstanding the foregoing, no Immaterial Subsidiary, Foreign Subsidiary
     or TCAS Subsidiary (except as provided below) of the Borrower shall be
     required to execute a Subsidiary Guarantee or Subsidiary Pledge Agreement,
     and no more than 65% of the Capital Stock of or equity interests in any
     Foreign Subsidiary of the Borrower or any of its Subsidiaries if more than
     65% of the assets of such Subsidiary are securities of foreign companies
     (such determination to be made on the basis of fair market value), shall be
     required to be pledged hereunder; provided, that if, after the consummation
     of the sale of a portion of Capital Stock of the TCAS Subsidiary to Thomson
     - CSF Sextant S.A. and/or an Affiliate thereof, the TCAS Subsidiary
     thereafter becomes a Wholly Owned Subsidiary, then the TCAS Subsidiary
     shall become a party to the Subsidiary Guarantee and Subsidiary Pledge
     Agreement and Borrower shall promptly (and in any event within 30 days
     after such event occurs) comply with the requirements of this subsection
     6.10(b) with respect to the TCAS Subsidiary.

     4.3 Section 6 of the Credit Agreement is hereby further amended by adding
the following new Subsection 6.15:

         6.15 TCAS Subsidiary. The Borrower shall at all times own, directly or
     indirectly, at least fifty-one percent (51%) of the Capital Stock of the
     TCAS Subsidiary; provided, that Borrower shall be permitted to sell all of
     the Capital Stock of the TCAS Subsidiary owned, directly or indirectly, by
     Borrower without violating the

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     terms of this subsection so long as the Net Proceeds resulting therefrom
     are applied in accordance with the terms of subsection 2.6(b)(ii) and (iv)
     hereof.

     4.4 Section 6 of the Credit Agreement is hereby further amended by adding
the following new Subsection 6.16:

         6.16 Required Distributions for TCAS Subsidiary. To the extent not
     prohibited under applicable law, cause the TCAS Subsidiary to distribute to
     the holders of Capital Stock of the TCAS Subsidiary not later than the 50th
     day after each fiscal quarter of Borrower for the immediately preceding
     fiscal quarter (i) all amounts necessary to fund tax obligations arising by
     virtue of the ownership of such Capital Stock ("Tax Distributions") and
     (ii) after giving effect to the funding of such quarterly Tax
     Distributions, all unrestricted cash on hand not needed to fund the
     anticipated working capital and capital expenditure needs of the TCAS
     Subsidiary.

     4.5 Subsection 7.4(f) to the Credit Agreement is hereby amended by deleting
the word "and" appearing at the end thereof and inserting in place thereof the
following additional language:

              "provided, that so long as the TCAS Subsidiary is not a Wholly
     Owned Subsidiary, no guarantee obligations by Borrower or any Subsidiary in
     respect of obligations of the TCAS Subsidiary shall be permitted under this
     clause (f) in excess of $3,000,000 at any time;"

4.6 Subsection 7.9(e) of the Credit Agreement is hereby amended by adding at the
end thereof the following additional language:

     "provided, that solely with respect to the TCAS Subsidiary at any time the
     TCAS Subsidiary is not a Wholly Owned Subsidiary, the aggregate amount of
     Investments by Borrower or any other Subsidiaries in the TCAS Subsidiary at
     any time (other than and in addition to the contribution to the TCAS
     Subsidiary by Borrower of (x) the assets related to the Acquired Company
     distributed on, or within 6 months after, the date of acquisition of the
     Acquired Company in an amount not to exceed the product of (a) the final
     purchase price paid by Borrower for the Acquired Company pursuant to the
     Acquisition Documents, after giving effect to any post-closing purchase
     price adjustments required pursuant to such Acquisition Documents and (b)
     the Borrower's percentage ownership interest in the TCAS Subsidiary and (y)
     subject to the written consent of the Agents, which shall not be
     unreasonably withheld or delayed, cash for the ongoing operating needs of
     the TCAS Subsidiary funded within 6 months after the date of acquisition of
     the Acquired Company), do not at any time exceed the greater of (i)
     $17,000,000 or (ii) the sum of $10,000,000 plus an amount equal to ten
     percent (10%) of the aggregate cash distributions received by Borrower from
     the TCAS Subsidiary during the immediately preceding 12-month period;"

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     SECTION 5. CONDITIONS TO EFFECTIVENESS FOR SECTION 2. The provisions of
Section 2 of this Amendment shall be deemed effective as of the date when each
of the following conditions have been satisfied (such effective date occurring
upon satisfaction of such conditions being referred to herein as the "FIRST
AMENDMENT EFFECTIVE DATE"):

     5.1 The Borrower shall have delivered to Administrative Agent executed
copies of this Amendment and each of the other Credit Parties shall have
delivered to the Administrative Agent executed copies of the Guarantors' Consent
and Acknowledgment to this Amendment in the form attached hereto;

     5.2 The Required Lenders shall have delivered to the Administrative Agent
an executed original or facsimile of a counterpart of this Amendment;

     5.3 The representations and warranties contained in Section 8 hereof shall
be true and correct in all respects;

     5.4 All fees and expenses owing to the Administrative Agent in connection
with this Amendment and/or the administration of the Credit Agreement, including
fees and disbursements of the Administrative Agent's counsel, shall have been
paid by Borrower; and

     5.5 All conditions to effectiveness set forth in Subsections 5.1-5.4 in
each of the Consent, Waiver and First Amendment to the Second Amended and
Restated Credit Agreement and the Consent, Waiver and First Amendment to the
Amended and Restated 364 Day Credit Agreement of even date herewith shall have
been satisfied.

     SECTION 6. CONDITIONS TO EFFECTIVENESS FOR SECTION 1.1 AND SECTION 3. The
provisions of Sections 1.1 and 3 of this Amendment shall be deemed effective as
of the date when each of the following conditions have been satisfied (such
effective date occurring upon satisfaction of such conditions being referred to
herein as the "PERMITTED CONVERTIBLE SECURITIES EFFECTIVE DATE"):

     6.1 The Requisite Class Lenders shall have delivered to the Administrative
Agent an executed original or facsimile of a counterpart of this Amendment;

     6.2 All conditions to the First Amendment Effective Date shall have been
satisfied;

     6.3 The representations and warranties contained in Section 8 hereof shall
be true and correct in all respects;

     6.4 Holdings shall have executed and delivered to the Administrative Agent
an amendment to the Parent Guarantee in form and substance reasonably
satisfactory to the Administrative Agent permitting Holdings to issue the
Permitted Convertible Securities;

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     6.5 All fees and expenses owing to the Administrative Agent in connection
with this Amendment and/or the administration of the Credit Agreement, including
fees and disbursements of the Administrative Agent's counsel, shall have been
paid by Borrower; and

     6.6 All conditions to effectiveness set forth in Subsections 6.1-6.5 in
each of the Consent, Waiver and First Amendment to the Second Amended and
Restated Credit Agreement and the Consent, Waiver and First Amendment to the
Amended and Restated 364 Day Credit Agreement of even date herewith shall have
been satisfied.

     SECTION 7. CONDITIONS TO EFFECTIVENESS FOR SECTION 1.2 AND SECTION 4. The
provisions of Sections 1.2 and 4 of this Amendment shall be deemed effective as
of the date when each of the following conditions have been satisfied (such
effective date occurring upon satisfaction of such conditions being referred to
herein as the "TCAS EFFECTIVE DATE"):

     7.1 All conditions to the First Amendment Effective Date shall have been
satisfied;

     7.2 The representations and warranties contained in Section 4 hereof shall
be true and correct in all respects;

     7.3 Thomson - CFS Sextant S.A. and/or an Affiliate thereof ("SEXTANT")
shall have purchased for cash no less than 30% of the Capital Stock of the TCAS
Subsidiary for a reciprocal percentage of the purchase price of the final
purchase price paid by the Borrower for the Acquired Company;

     7.4 The Administrative Agent shall have received a perfected first priority
pledge of the Capital Stock of the TCAS Subsidiary owned by Borrower in favor of
the Administrative Agent for the ratable benefit of the Lenders, the Facility A
Lenders and the Facility B Lenders pursuant to a LLC pledge agreement and
related financing statement (collectively, the "LLC PLEDGE DOCUMENTS") in form
and substance reasonably satisfactory to the Administrative Agent;

     7.5 The Administrative Agent shall have received an opinion of counsel to
the Borrower in form and substance reasonably satisfactory to the Administrative
Agent;

     7.6 The Administrative Agent shall have received a final executed copy of
the limited liability company operating agreement of the TCAS Subsidiary which
shall be in form and substance reasonably satisfactory to the Administrative
Agent;

     7.7 The Administrative Agent shall have received a secretary's or assistant
secretary's certificate of Borrower certifying the board resolutions authorizing
the execution, delivery and performance of this Amendment and the LLC Pledge
Documents;

     7.8 All fees and expenses owing to the Administrative Agent in connection
with this Amendment and/or the administration of the Credit Agreement, including
fees and disbursements of the Administrative Agent's counsel, shall have been
paid by Borrower;

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     7.9 The Administrative Agent shall have received a certificate of a
Responsible Officer of Borrower certifying and confirming the consummation of
the Sextant investment described in Subsection 7.3 above and satisfaction of all
other conditions to effectiveness set forth in this Section 7; and

     7.10 All conditions to effectiveness set forth in Subsections 7.1-7.9 in
each of the Consent, Waiver and First Amendment to the Second Amended and
Restated Credit Agreement and the Consent, Waiver and First Amendment to the
Amended and Restated 364 Day Credit Agreement of even date herewith shall have
been satisfied.

     SECTION 8. REPRESENTATIONS AND WARRANTIES. In order to induce Lenders to
enter into this Amendment and to amend the Credit Agreement in the manner
provided herein, the Borrower represents and warrants to each Lender that the
following statements are true, correct and complete:

     8.1 Authorization and Enforceability. (a) The Borrower has all requisite
corporate power and authority to enter into this Amendment and the LLC Pledge
Documents and to carry out the transactions contemplated by, and perform its
obligations under, the Credit Agreement as amended by this Amendment (the
"AMENDED AGREEMENT") and the LLC Pledge Documents, (b) the execution and
delivery of this Amendment and the LLC Pledge Documents has been duly authorized
by all necessary corporate action on the part of the Borrower and (c) this
Amendment, the Amended Agreement and the LLC Pledge Documents have been duly
executed and delivered by the Borrower and, when executed and delivered, will be
the legally valid and binding obligations of the Borrower, enforceable against
the Borrower in accordance with their respective terms, subject to (i) the
effects of bankruptcy, insolvency, fraudulent conveyance, reorganization,
moratorium or similar laws relating to or limiting creditors' rights generally,
(ii) general equitable principles (whether considered in a proceeding, in equity
or at law) and (iii) an implied covenant of good faith and fair dealing.

     8.2 Incorporation of Representations and Warranties From Credit Agreement.
The representations and warranties contained in Section 4 of the Credit
Agreement are and will be true, correct and complete in all material respects on
and as of the First Amendment Effective Date, the Permitted Convertible
Securities Effective Date and the TCAS Effective Date to the same extent as
though made on and as of that date, except to the extent such representations
and warranties specifically relate to an earlier date, in which case they were
true, correct and complete in all material respects on and as of such earlier
date.

     8.3 Absence of Default. No event has occurred and is continuing or will
result from the consummation of the transactions contemplated by this Amendment
that would constitute an Event of Default or a potential Event of Default.

     SECTION 9. MISCELLANEOUS.

     9.1 Effect on the Credit Agreement and the other Credit Documents. Except
as specifically amended by this Amendment, the Credit Agreement and the other
Credit Documents shall remain in full force and effect and are hereby ratified
and confirmed. The

                                       11
<PAGE>

execution, delivery and performance of this Amendment shall not, except as
expressly provided herein, constitute a waiver of any provision of, or operate
as a waiver of any right, power or remedy of the Administrative Agent or any
Lender under, the Credit Agreement or any of the other Credit Documents.

     9.2 Fees and Expenses. The Borrower acknowledges that all costs, fees and
expenses as described in Section 10.5 of the Credit Agreement incurred by
Administrative Agent and its counsel with respect to this Amendment and the
documents and transactions contemplated hereby shall be for the account of the
Borrower.

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

     9.4 SUBMISSION TO JURISDICTION; WAIVERS; WAIVER OF JURY TRIAL;
ACKNOWLEDGMENTS; CONFIDENTIALITY. Each of the terms and conditions set forth in
Sections 10.12, 10.13, 10.14 and 10.15 of the Credit Agreement are hereby
incorporated into this Amendment as if set forth fully herein except that each
reference to "Agreement" therein shall be deemed to be a reference to
"Amendment" herein.

     9.5 Counterparts; Effectiveness. This Amendment may be executed in any
number of counterparts and by different parties hereto in separate counterparts,
each of which when so executed and delivered shall be deemed an original, but
all such counterparts together shall constitute but one and the same instrument.
Except for the terms of Sections 1, 2, 3 and 4 hereof (which shall only become
effective on the First Amendment Effective Date, the Permitted Convertible
Securities Effective Date and/or the TCAS Effective Date, as applicable), this
Amendment shall become effective upon the execution of a counterpart hereof by
the Borrower, the Required Lenders, the Syndication Agent, the Documentation
Agent and the Administrative Agent and receipt by the Borrower and the
Administrative Agent of written or telephonic notification of such execution and
authorization of delivery thereof.



                            [SIGNATURE PAGES FOLLOW]


<PAGE>


     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and delivered by their proper and duly authorized officers as of
the day and year first above written.

                                   L-3 COMMUNICATIONS CORPORATION

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


                                   LEHMAN COMMERCIAL PAPER INC.,
                                     as Documentation Agent, Syndication Agent,
                                     and as a Lender

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


                                   BANK OF AMERICA, N.A.,
                                     as Administrative Agent

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


                                  BANK OF AMERICA, N.A.,
                                    as a Lender

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



           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                      THE BANK OF NEW YORK

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          THE BANK OF NOVA SCOTIA

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          BANK ONE, NA

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          CREDIT LYONNAIS NEW YORK BRANCH

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>


                                          FIRST UNION COMMERCIAL CORPORATION

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          BANK AUSTRIA CREDITANSTALT
                                          CORPORATE FINANCE INC.

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>


                                          THE GOVERNOR AND COMPANY OF THE
                                          BANK OF IRELAND

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          BANK OF TOKYO-MITSUBISHI TRUST COMPANY

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          COMERICA BANK

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>



                                          CREDIT INDUSTRIEL ET COMMERCIAL

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>


                                          THE DAI-ICHI KANGYO BANK, LTD.

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>


                                          DG BANK
                                          DEUTSCHE GENOSSENSCHAFTSBANK AG

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          DRESDNER BANK AG, NEW YORK AND GRAND
                                          CAYMAN BRANCHES

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          ERSTE BANK, NEW YORK

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          GE CAPITAL COMMERCIAL FINANCE, INC

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          THE INDUSTRIAL BANK OF JAPAN, LIMITED

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          MEES PIERSON CAPITAL CORP.

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          THE MITSUBISHI TRUST AND
                                          BANKING CORPORATION

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          NATIONAL CITY BANK

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          THE ROYAL BANK OF SCOTLAND PLC

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          SOCIETE GENERALE

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          SUMMIT BANK

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          WEBSTER BANK

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          DEN DANSKE BANK AKTIESELSKAB
                                          CAYMAN ISLANDS BRANCH

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          MERITA BANK PLC

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


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









           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                                          SUNTRUST BANK

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>
                                          BANQUE WORMS CAPITAL CORPORATION

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








           [SIGNATURE PAGES TO CONSENT, WAIVER AND FIRST AMENDMENT TO
                         NEW 364 DAY CREDIT AGREEMENT]

<PAGE>

                     Guarantors' Acknowledgment and Consent
                     --------------------------------------

     Each of the undersigned hereby acknowledges receipt of the attached
Amendment and consents to the execution and performance thereof by L-3
Communications Corporation. Each of the undersigned hereby also reaffirms that
the guarantee of such undersigned in favor of the Administrative Agent for the
ratable benefit of the Lenders and the Agents remains in full force and effect
and acknowledges and agrees that there is no defense, setoff or counterclaim of
any kind, nature or description to obligations arising under such guarantee.

Dated: ____ ___, 2000

                                        L-3 COMMUNICATIONS HOLDINGS, INC.

                                        By:
                                           -------------------------------------
                                           Name: Christopher C. Cambria
                                           Title: Vice President-General Counsel
                                                  and Secretary



                                        HYGIENETICS ENVIRONMENTAL SERVICES, INC.


                                        By:
                                           -------------------------------------
                                           Name: Christopher C. Cambria
                                           Title: Vice President and Secretary



                                        L-3 COMMUNICATIONS ILEX SYSTEMS, INC.


                                        By:
                                           -------------------------------------
                                           Name: Christopher C. Cambria
                                           Title: Vice President and Secretary



                                        L-3 COMMUNICATIONS SPD TECHNOLOGIES INC.


                                        By:
                                           -------------------------------------
                                           Name: Christopher C. Cambria
                                           Title: Vice President and Secretary





      [GUARANTORS' ACKNOWLEDGMENT AND CONSENT TO CONSENT, WAIVER AND FIRST
                   AMENDMENT TO NEW 364 DAY CREDIT AGREEMENT]



<PAGE>



                                          L-3 COMMUNICATIONS AYDIN
                                          CORPORATION


                                          By:
                                             -----------------------------------
                                             Name: Christopher C. Cambria
                                             Title: Vice President and Secretary



                                          MICRODYNE CORPORATION



                                          By:
                                             -----------------------------------
                                             Name: Christopher C. Cambria
                                             Title: Vice President and Secretary







      [GUARANTORS' ACKNOWLEDGMENT AND CONSENT TO CONSENT, WAIVER AND FIRST
                   AMENDMENT TO NEW 364 DAY CREDIT AGREEMENT]