<PAGE>


                         L-3 COMMUNICATIONS CORPORATION

                          CONSENT AND SECOND AMENDMENT
                         TO NEW 364-DAY CREDIT AGREEMENT

         This CONSENT AND SECOND AMENDMENT TO THE NEW 364-DAY CREDIT AGREEMENT
(this "AMENDMENT") is dated as of November 16, 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 the waiver of
certain prepayment requirements and 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. CONSENT TO LIMITED WAIVER. Borrower has requested that the
Required Class Lenders consent to a waiver of the mandatory prepayment of the
Loans and permanent reduction in Commitments required by Section 2.6(b)(i) of
the Credit Agreement with respect to the Net Proceeds of Indebtedness incurred
in connection with the issuance of up to the Designated Issue Amount (as defined
herein) of Permitted Convertible Securities (the "Requested Waiver"). Subject to
the satisfaction of the conditions precedent to this Amendment set forth in
Section 3 hereof, each Lender executing this Amendment hereby consents to the
Requested Waiver. As used herein, "Designated Issue Amount" shall mean the
aggregate principal amount of Permitted Convertible Securities actually issued
on or prior to January 31, 2001, which shall not in any event exceed
$300,000,000.
<PAGE>

         SECTION 2. AMENDMENTS. Subject to the satisfaction of each of the
conditions to effectiveness set forth in Section 3 of this Amendment, the
Borrower and the Lenders hereby agree to amend the Credit Agreement as follows:

         2.1 The definition of "New Investment Sublimit" appearing in subsection
1.1 of the Credit Agreement is hereby amended by deleting the term
"$650,000,000" and inserting the term "$850,000,000" in place thereof.

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

         "Second Amendment Effective Date": shall have the meaning given to such
term in that certain Consent and Second Amendment to the New 364-Day Credit
Agreement dated as of November 16, 2000.

         2.3 Subsection 2.18 of the Credit Agreement is hereby amended by adding
at the end thereof the following additional language:

                  "Subject to the occurrence of the Second Amendment Effective
         Date, Borrower hereby agrees to pay to each Lender submitting to the
         Administrative Agent an executed counterpart to the Second Amendment to
         this Agreement on or before 12:00 (noon) (New York time) on November
         29, 2000 (a "Second Amendment Lender") a non-refundable amendment fee
         (the "Second Amendment Fee") in an amount equal to 5 basis points
         multiplied by the Commitment of such Lender under the Credit Agreement.
         The Second Amendment Fee owing to each Second Amendment Lender shall be
         paid in immediately available funds by the Borrower to the
         Administrative Agent for the benefit of such Second Amendment Lenders
         not later than noon (New York time) on the first Business Day following
         the occurrence of the Second Amendment Effective Date."

         2.4 Subsection 7.4(h) of the Credit Agreement is hereby amended and
restated in its entirety to read as follows:

                  (h) Guarantee Obligations in respect of up to $400,000,000
         principal amount of Convertible Securities issued by Holdings having an
         initial annual interest rate not in excess of 7% per annum which
         initial annual interest rate may be subject to subsequent adjustments
         in accordance with the terms of such Convertible Securities in the
         event of a Reset Transaction (the "Permitted Convertible Securities").
         As used herein, a "Reset Transaction" shall have the meaning ascribed
         to such term in the Indenture governing the issuance of the Convertible
         Senior Subordinated Notes of Holdings due 2009 as in effect at the time
         of such issuance.

         2.5 Subsection 7.9(e) of the Credit Agreement is hereby amended by
deleting the term "6 months" each place it appears therein, and inserting the
term "12 months" in place thereof.

                                       2
<PAGE>

         SECTION 3. CONDITIONS TO EFFECTIVENESS. Sections 1 and 2 of this
Amendment shall be deemed effective as of the date when each of the following
conditions precedent have been satisfied (such effective date occurring upon
satisfaction of such conditions precedent being referred to herein as the
"SECOND AMENDMENT EFFECTIVE DATE"):

         3.1. The Required Class Lenders shall have delivered to the
Administrative Agent an executed original or facsimile of a counterpart of this
Amendment, the Second Amendment to the Second Amended and Restated Credit
Agreement of even date herewith and the Third Amendment to the Amended and
Restated 364 Day Credit Agreement of even date herewith.

         3.2. The Borrower shall have delivered to the 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.

         3.3. All fees owing to the Administrative Agent by the Borrower and all
attorneys fees and disbursements incurred by the Agents in connection with the
administration of the Credit Agreement and/or this Amendment shall have been
paid.

         3.4. The Administrative Agent shall have received a secretary's or
assistant secretary's certificate of Borrower certifying board resolutions
authorizing the execution, delivery and performance of this Amendment by
Borrower.

         3.5. The representations and warranties contained in Section 4 hereof
shall be true and correct in all respects.

         3.6. All conditions set forth in Sections 3.1 through 3.5 of the Second
Amendment to the Second Amended and Restated Credit Agreement of even date
herewith and the Third Amendment to the Amended and Restated 364 Day Credit
Agreement of even date herewith shall have been satisfied.

         SECTION 4. 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:

         4.1. Authorization and Enforceability. (a) The Borrower has all
requisite corporate power and authority to enter into this Amendment and to
carry out the transactions contemplated by, and perform its obligations under,
the Credit Agreement as amended by this Amendment (the "AMENDED AGREEMENT"), (b)
the execution and delivery of this Amendment has been duly authorized by all
necessary corporate action on the part of the Borrower and (c) this Amendment
and the Amended Agreement 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, except


                                       3
<PAGE>

as may be limited by bankruptcy, insolvency, reorganization, moratorium or
similar laws relating to or limiting creditors' rights generally or by equitable
principles relating to enforceability.

                  4.2. 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 Second Amendment 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.

                  4.3. Absence of Default and Setoff. 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 and no defense, setoff or counterclaim of any kind,
nature or description exists to the payment and performance of the obligations
owing by Borrower to the Agents and the Lenders.

                  SECTION 5. MISCELLANEOUS.

                  5.1. 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 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.

                  5.2. 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.

                  5.3. GOVERNING LAW. THIS AGREEMENT 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.

                  5.4. 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.

                  5.5. 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


                                       4
<PAGE>

shall constitute but one and the same instrument. Except for the terms of
Sections 1 and 2 hereof (which shall only become effective on the Second
Amendment Effective Date), this Amendment shall become effective upon the
execution of a counterpart hereof by the Borrower and the Required Lenders 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]


                                       5
<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:      /s/ Lawrence O'Brien
                                 ----------------------------------------------
                                 Title: Vice-President and Treasurer


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


                              By:      /s/Liliana Claar
                                 ----------------------------------------------
                                 Title: Vice President


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


                              By:      /s/ Lisa Choi
                                 ----------------------------------------------
                                 Title: Vice President


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


                              By:      /s/ G. Andrew Keith
                                 ----------------------------------------------
                                 Title: Authorized Signatory



               [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO
                          NEW 364 DAY CREDIT AGREEMENT]


<PAGE>

                              THE BANK OF NOVA SCOTIA


                              By:      /s/ Todd S. Meller
                                 ----------------------------------------------
                                 Title: Managing Director





         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              BANK ONE, NA


                              By:      /s/ Andrea S. Kantor
                                 ----------------------------------------------
                                 Title: First Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>




                              CREDIT LYONNAIS NEW YORK BRANCH


                              By:      /s/ Scott R. Chappelka
                                 ----------------------------------------------
                                 Title: Vice President


         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]




<PAGE>



                              FIRST UNION COMMERCIAL CORPORATION


                              By:      /s/ Barbara Van Meerten
                                 ----------------------------------------------
                                 Title: Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              BANK AUSTRIA CREDITANSTALT
                              CORPORATE FINANCE INC.


                              By:      /s/ Ridgely H. Cromwell
                                 ----------------------------------------------
                                 Title: Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              THE GOVERNOR AND COMPANY OF THE
                              BANK OF IRELAND


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



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              BANK OF TOKYO-MITSUBISHI TRUST COMPANY


                              By:      /s/ Chris Droussiotis
                                 ----------------------------------------------
                                 Title: Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              COMERICA BANK


                              By:      /s/ Joel Gordon
                                 ----------------------------------------------
                                 Title: Account Officer



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>




                              CREDIT INDUSTRIEL ET COMMERCIAL


                              By: /s/ Brian O'Leary           /s/ Marcus Edward
                                 ----------------------------------------------
                                 Title: Vice Presidents



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              THE DAI-ICHI KANGYO BANK, LTD.


                              By:      /s/ Charles Partnel
                                 ----------------------------------------------
                                 Title: Senior Vice President


         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]




<PAGE>


                              DG BANK
                              DEUTSCHE GENOSSENSCHAFTSBANK AG


                              By: /s/ Stephen A. Santora  /s/ Richard W. Wilbert
                                 ----------------------------------------------
                                 Title: Vice Presidents



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              DRESDNER BANK AG, NEW YORK AND GRAND
                              CAYMAN BRANCHES


                              By:  /s/ James Y. Hua         /s/ Bo Andersen
                                 ----------------------------------------------
                                 Title: Vice Presidents



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              ERSTE BANK, NEW YORK


                              By:      /s/ Arinee Hovanessian
                                 ----------------------------------------------
                                 Title: Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              GE CAPITAL COMMERCIAL FINANCE, INC


                              By:      /s/ William S. Richardson
                                 ----------------------------------------------
                                 Title: Duly Authorized Signatory



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              THE INDUSTRIAL BANK OF JAPAN, LIMITED


                              By:      /s/J. Kenneth Biegen
                                 ----------------------------------------------
                                 Title: Senior Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              MEES PIERSON CAPITAL CORP.


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



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              THE MITSUBISHI TRUST AND
                              BANKING CORPORATION


                              By:      /s/ Rosetta Conti
                                 ----------------------------------------------
                                 Title: Senior Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              NATIONAL CITY BANK


                              By:      /s/ Wilmer J. Jacobs
                                 ----------------------------------------------
                                 Title: Assistant Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              THE ROYAL BANK OF SCOTLAND PLC


                              By:      /s/ Jayne Seaford
                                 ----------------------------------------------
                                 Title: Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              SOCIETE GENERALE


                              By:      /s/ Jose A. Moreno
                                 ----------------------------------------------
                                 Title: Director



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              SUMMIT BANK


                              By:      /s/Ricard J. Banning
                                 ----------------------------------------------
                                 Title: Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              WEBSTER BANK


                              By:      /s/ John Gilsenan
                                 ----------------------------------------------
                                 Title: Vice President



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>




                              DEN DANSKE BANK AKTIESELSKAB
                              CAYMAN ISLANDS BRANCH


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



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>



                              MERITA BANK PLC


                              By:      /s/ Michael J. Maher
                                 ----------------------------------------------
                                 Title: Senior Vice President

                              By:      /s/ Garry Weiss
                                 ----------------------------------------------
                                 Title: Vice President


         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]




<PAGE>



                              SUNTRUST BANK


                              By:      /s/ Armen Karozichian
                                 ----------------------------------------------
                                 Title:



         [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO NEW 364 DAY
                               CREDIT AGREEMENT]



<PAGE>




                              BANQUE WORMS CAPITAL CORPORATION


                              By:      /s/H. Fleming
                                 ----------------------------------------------
                                 Title: V.P. & General Counsel



         [SIGNATURE PAGES TO CONSENT AND SECOND 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: _Nov 16, 2000

                               L-3 COMMUNICATIONS HOLDINGS, INC.


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


                               HYGIENETICS ENVIRONMENTAL SERVICES, INC.


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


                               L-3 COMMUNICATIONS ILEX SYSTEMS, INC.


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


                               L-3 COMMUNICATIONS SPD TECHNOLOGIES INC.


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



         [GUARANTORS' ACKNOWLEDGMENT AND CONSENT AND SECOND AMENDMENT TO
                          NEW 364 DAY CREDIT AGREEMENT]


<PAGE>



                               L-3 COMMUNICATIONS AYDIN


                               CORPORATION


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


                               MICRODYNE CORPORATION


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






              [SIGNATURE PAGES TO CONSENT AND SECOND AMENDMENT TO
                 SECOND AMENDED AND RESTATED CREDIT AGREEMENT]