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                                                                   EXHIBIT 10.58





                           FIRST AMENDMENT AGREEMENT

                         Dated as of December 30, 1996

                                     among

                            LCC INTERNATIONAL, INC.

                          LCC DESIGN SERVICES, L.L.C.

                        LCC DEVELOPMENT COMPANY, L.L.C.

                          THE LENDERS SIGNATORY HERETO

                                      and

                            THE CHASE MANHATTAN BANK

                            as Administrative Agent
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                           FIRST AMENDMENT AGREEMENT

         FIRST AMENDMENT AGREEMENT dated as of December 30, 1996 among LCC
INTERNATIONAL, INC., a corporation organized under the laws of Delaware (the
"Borrower"); LCC DESIGN SERVICES, L.L.C., a limited liability company organized
under the laws of Delaware, and LCC DEVELOPMENT COMPANY, L.L.C., a limited
liability company organized under the laws of Delaware (collectively, the
"Subsidiary Guarantors" and, together with the Borrower, the "Obligers"); each
of the financial institutions which is a signatory hereto as a "Lender"
(collectively the "Lenders"); and THE CHASE MANHATTAN BANK, a bank organized
under the laws of New York, as administrative agent for the Lenders (in such
capacity, together with its successors in such capacity, the "Administrative
Agent").

         WHEREAS, the Borrower, the Subsidiary Guarantors, the Lenders and the
Administrative Agent have entered into that certain Amended and Restated Credit
Agreement dated as of September 30, 1996 (as in effect prior to the
effectiveness of this Agreement, the "Existing Credit Agreement," and, as
amended by this Agreement, the "Amended Credit Agreement") pursuant to which
the Lenders have extended credit to the Obligers evidenced by certain
Promissory Notes dated September 30, 1996 issued by the Borrower and guarantied
by the Subsidiary Guarantors;

         WHEREAS, the Borrower, the Subsidiary Guarantors, the Lenders and the
Administrative Agent have agreed to enter into this Agreement to provide for,
among other things, the modification of certain covenants and definitions
contained in the Existing Credit Agreement; and

         WHEREAS, the Facility Documents, as amended and supplemented by this
Agreement (including, without limitation, this Agreement and the Amended Credit
Agreement) and as each may be amended or supplemented from time to time, are
referred to herein as the "Amended Facility Documents".

         NOW THEREFORE, for valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the parties hereto agree as follows:

                 ARTICLE 1.  AMENDMENTS TO EXISTING CREDIT AGREEMENT.

         Each of the Obligers and, subject to the satisfaction of the
conditions set forth in Article 3, the Administrative Agent and the Lenders
hereby consents and agrees to the amendments to the Existing Credit Agreement
set forth below:





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                 (a)      The definition of "Consolidated EBITDA" in Section
1.01 of the Existing Credit Agreement is hereby amended and restated in its
entirety to read as follows:

                 "Consolidated EBITDA" means, with respect to any fiscal
         period, the sum of (a) Consolidated EDIT for such period, plus (b) the
         aggregate amount of (i) depreciation and amortization expense, (ii)
         non-cash accruals under the Phantom Membership Plan, (iii) in process
         research and development expense related to the purchase of all the
         assets of European Technology Partner AS up to $5,605,000 and (iv)
         reserves taken during the Fiscal Year ending on December 31, 1996
         against receivables, promissory notes and investments in DC and
         NextWave up to $30,050,000, to the extent that such aggregate amount
         was deducted in the computation of Consolidated EDIT for such period.

                 (b)      The definition of "Consolidated Intangible Assets" in
Section 1.01 of the Existing Credit Agreement is hereby amended to insert "but
in any event excluding, for the Fiscal Quarter ending on December 31, 1996, up
to $250,000 of contract rights acquired by Microcell Management, Inc."
immediately subsequent to "other similar intangible assets" in such definition.

                 (c)      The definition of "Consolidated Net Income" in
Section 1.01 of the Existing Credit Agreement is hereby amended and restated in
its entirety to read as follows:

                 "Consolidated Net Income" means, with respect to any fiscal
         period, net income of the Consolidated Entities for such period (but
         in any event excluding income resulting from the reversal of reserves
         taken against receivables, promissory notes or investments in DC or
         NextWave), as determined on a consolidated basis in accordance with
         GAP.

                 (d)      The definition of "Fiscal Quarter Net Worth Increase
Amounts" in Section 1.01 of the Existing Credit Agreement is hereby amended to
add "plus (c) 100% of  income resulting from the reversal of reserves taken
against receivables, promissory notes or investments in DC or NextWave during
such Fiscal Quarter" immediately prior to the end of such definition.

                 (e)      Section 9.02 of the Existing Credit Agreement is
hereby amended to substitute "(a) $48,000,000" in place of "(a)(i) if such time
is before December 31, 1996, $64,000,000 or (ii) if such time is on or after
December 31, 1996, $69,000,000".

                 (f)      Section 9.03 of the Existing Credit Agreement is
hereby amended to substitute "(a) if such time is before March 31, 1997, 1.65
to 1.00 or (b) if such time is on or after March 31, 1997, 1.75 to 1.00" in
place of "1.75 to 1.00".





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                 ARTICLE 2.  REPRESENTATIONS AND WARRANTIES.

         Each of the Obligers hereby represents and warrants that as of the
Effective Date:

         Section 2.1.     Existing Representations and Warranties.  Each of the
representations and warranties contained in Article 6 of the Existing Credit
Agreement and in each of the other Facility Documents are true and correct.

         Section 2.2.     No Defaults.   No event has occurred and no condition
exists which would constitute a Default or an Event of Default under the
Facility Documents, and no event has occurred and no condition exists which
would constitute a Default or an Event of Default under the Amended Facility
Documents.

         Section 2.3.     Power and Authority; No Conflicts.  The execution,
delivery and performance by each of the Obligers of the Amended Facility
Documents to which it is a party have been duly authorized by all necessary
corporate, partnership and limited liability company action and do not and will
not: (a) require any consent or approval of its members which has not been
obtained; (b) contravene its organizational documents; (c) violate any
provision of, or require any filing (other than the filings required pursuant
to the terms of the Security Documents), registration, consent or approval
under, any law, rule, regulation (including, without limitation, Regulation U),
order, writ, judgment, injunction, decree, determination or award presently in
effect having applicability to the Parent or any of its Subsidiaries; (d)
result in a breach of or constitute a default or require any consent under any
indenture or loan or credit agreement, or any other agreement, lease or
instrument to which the Parent or any of its Subsidiaries is a party or by
which their respective Properties may be bound or affected; (e) result in, or
require, the creation or imposition of any Lien (other than as created under
the Security Documents), upon or with respect to any of the Properties now
owned or hereafter acquired by the Parent or any of its Subsidiaries; or (f)
cause the Parent or any of its Subsidiaries to be in default under any such
law, rule, regulation, order, writ, judgment, injunction, decree, determination
or award or any such indenture, agreement, lease or instrument.

         Section 2.4.     Legally Enforceable Agreements.  Each Amended
Facility Document to which any Obligor is a party has been duly executed and
delivered by such Obligor.  Each Amended Facility Document to which any Obligor
is a party a legal, valid and binding obligation of such Obligor enforceable
against such Obligor in accordance with its terms, except to the extent that
such enforcement may be limited by applicable bankruptcy, insolvency and other
similar laws affecting creditors' rights generally and general principles of
equity (regardless of whether such enforceability is considered in a proceeding
at law or in equity).





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         Section 2.5.  Financial Statements. The consolidated balance sheets of
the Borrower and its Subsidiaries as at December 31, 1996, 1995 and 1994, and
the related consolidated statements of income, cash flows and shareholders'
equity (or members' capital) of the Borrower and its Subsidiaries, for the
Fiscal Years then ended, and the accompanying footnotes, together with the
opinion on the consolidated statements of KPMG Peat Marwick, independent
certified public accountants, copies of which have been furnished to each of
the Lenders, are complete and correct in all material respects and fairly
present the financial condition of the LCC Consolidated Entities at such dates
and the results of the operations of the LCC Consolidated Entities for the
periods covered by such statements, all in accordance with GAP consistently
applied.  There are no liabilities of any LCC Consolidated Entity, fixed or
contingent, which are material but are not reflected in such financial
statements or in such notes and which would be required to be recorded in such
financial statements or notes in accordance with GAP.  No information, exhibit
or report furnished by any LCC Consolidated Entity to the Administrative Agent
or any Lender in connection with the negotiation of this Agreement or any other
Amended Facility Document contained any material misstatement of fact or
omitted to state a material fact or any fact necessary to make the statements
contained therein not materially misleading.  Since December 31, 1996, there
has been no change which could reasonably be expected to have a Material
Adverse Effect.

                 ARTICLE 3.  CONDITIONS PRECEDENT.

         The effectiveness of this Agreement is subject to the condition
precedent that the Administrative Agent shall have received on or before April
15, 1997 (the "Effective Date") each of the following, in form and substance
satisfactory to the Administrative Agent and its counsel:

                 (a)      counterparts of this Agreement executed by each of
the Borrower, the Subsidiary Guarantors, the Lenders and the Administrative
Agent; and

                 (b)      certified complete and correct copies of each of the
financial statements referred to in Section 2.05.

                 ARTICLE 4.  MISCELLANEOUS.

         Section 4.1.     Defined Terms.  The terms used herein and not defined
herein shall have the meanings assigned to such terms in the Amended Credit
Agreement.





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         Section 4.2.     Nonwaiver.  Except for the foregoing waivers, the
terms of this Agreement shall not operate as a waiver by the Administrative
Agent or any Lender or otherwise prejudice the rights, remedies or powers of
the Administrative Agent or any Lender under the Amended Credit Agreement,
under any other Amended Facility Document or under applicable law.  Except as
expressly provided herein: (x) no terms and provisions of the Facility
Documents are modified or changed by this Agreement; and (y) the terms and
provisions of the Facility Documents shall continue in full force and effect.

         Section 4.3.     Reaffirmation.  Each of the Obligers acknowledges
that the Liens granted to the Administrative Agent under the Security Documents
in and to the Collateral secures all of the Obligations.  Each of the Obligers
further acknowledges and reaffirms all of its other respective obligations and
duties under the Amended Facility Documents to which it is a party.

         Section 4.4.     Amendments and Waivers.  Any provision of this
Agreement may be amended or modified only by an instrument in writing signed by
the Borrower, the Administrative Agent and the Required Lenders, or by the
Borrower and the Administrative Agent acting with the consent of the Required
Lenders and any provision of this Agreement may be waived by the Required
Lenders or by the Administrative Agent acting with the consent of the Required
Lenders.

         Section 4.5.     Expenses.  The Borrower shall reimburse the
Administrative Agent on demand for all reasonable costs, expenses and charges
(including, without limitation, reasonable fees of counsel to the
Administrative Agent) in connection with the preparation of, and any amendment,
supplement, waiver or modification to (in each case, whether or not
consummated), this Agreement, any other Amended Facility Document and any other
documents prepared in connection herewith or therewith.

         Section 4.6.     Notices.  Unless the party to be notified otherwise
notifies the other party in writing as provided in this Section, and except as
otherwise provided in this Agreement, notices shall be given in writing to the
Administrative Agent, to the Lenders, to the Borrower and to the Subsidiary
Guarantors by ordinary mail, hand delivery, overnight courier or telecopier
addressed to such party at its address on the signature page of this Agreement.
Notices shall be effective: (a) if given by mail, 72 hours after deposit in the
mails with first class postage prepaid, addressed as aforesaid; and (b) if
given by telecopier, when the telecopy is transmitted to the telecopier number
as aforesaid; provided that notices to the Administrative Agent shall be
effective upon receipt.





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         Section 4.7.     Headings.  The headings and captions hereunder are
for convenience only and shall not affect the interpretation or construction of
this Agreement.

         Section 4.8.     Severability.  The provisions of this Agreement are
intended to be severable.  If for any reason any provision of this Agreement
shall be held invalid or unenforceable in whole or in part in any jurisdiction,
such provision shall, as to such jurisdiction, be ineffective to the extent of
such invalidity or unenforceability without in any manner affecting the
validity or enforceability thereof in any other jurisdiction or the remaining
provisions hereof in any jurisdiction.

         Section 4.9.     Counterparts.  This Agreement may be executed in any
number of counterparts, all of which taken together shall constitute one and
the same instrument, and any party hereto may execute this Agreement by signing
any such counterpart.

         Section 4.10.    Integration.  The Amended Facility Documents set
forth the entire agreement among the parties hereto relating to the
transactions contemplated thereby and supersede any prior oral or written
statements or agreements with respect to such transactions.

         SECTION 4.11.    GOVERNING LAW.  THIS AGREEMENT SHALL BE GOVERNED BY,
AND INTERPRETED AND CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW
YORK.





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         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed as of the day and year first above written.


                                    BORROWER:
                                    
                                    LCC INTERNATIONAL, INC., A DELAWARE
                                      CORPORATION
                                    
                                    
                                    By  /s/ RICHARD HOZIK
                                      ----------------------------------------
                                             Name:  Richard Hozik
                                             Title: Senior Vice President, 
                                                    Treasurer and Chief
                                                    Operating Officer
                                    
                                    
                                    
                                       Address for Notices:
                                    
                                       7925 Jones Branch Drive
                                       McLean, Virginia 22102
                                       Attention: Chief Financial Officer
                                       Telecopier No.: (703) 873-2100
                                    
                                       with a copy to:
                                    
                                       7925 Jones Branch Drive
                                       McLean, Virginia 22102
                                       Attention: General Counsel
                                       Telecopier No.: (703) 873-2100






                 [SIGNATURE PAGE TO FIRST AMENDMENT AGREEMENT]
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                                    SUBSIDIARY GUARANTORS:
                                    
                                    
                                    LCC DESIGN SERVICES, L.L.C., A DELAWARE
                                      LIMITED LIABILITY COMPANY
                                    
                                    
                                    By /s/ RICHARD HOZIK
                                      -----------------------------------------
                                             Name:  Richard Hozik
                                             Title:
                                    
                                    
                                    LCC DEVELOPMENT COMPANY, L.L.C.,
                                      A DELAWARE LIMITED LIABILITY COMPANY
                                    
                                    
                                    
                                    By /s/ RICHARD HOZIK
                                      ----------------------------------------
                                             Name:  Richard Hozik
                                             Title:
                                    
                                    
                                    
                                       Address for Notices:
                                    
                                       c/o LCC International, Inc.
                                       7925 Jones Branch Drive
                                       McLean, Virginia 22102
                                       Attention: Chief Financial Officer
                                       Telecopier No.: (703) 873-2100
                                    
                                       with a copy to:
                                    
                                       c/o LCC International, Inc.
                                       7925 Jones Branch Drive
                                       McLean, Virginia 22102
                                       Attention: General Counsel
                                       Telecopier No.: (703) 873-2100






                 [SIGNATURE PAGE TO FIRST AMENDMENT AGREEMENT]
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                                    ADMINISTRATIVE AGENT:
                                    
                                    THE CHASE MANHATTAN BANK
                                    
                                    
                                    
                                    By /s/ ALAN ARIA
                                      -----------------------------------------
                                             Name: Alan Aria
                                             Title:
                                    
                                       Address for Notices:
                                    
                                       4 Chase Metrotech Center
                                       13th Floor
                                       Brooklyn, NY 11245
                                       Attention: New York Agency
                                    
                                    
                                       with a copy to:
                                       999 Broad Street
                                       Bridgeport, Connecticut 06604
                                       Attention: Alan Aria






                 [SIGNATURE PAGE TO FIRST AMENDMENT AGREEMENT]
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                                    LENDERS:
                                    
                                    THE CHASE MANHATTAN BANK
                                    
                                    
                                    
                                    By  /s/ ALAN ARIA
                                      -----------------------------------------
                                             Name: Alan Aria
                                             Title:
                                    
                                    
                                       Lending Office and Address for
                                       Notices:
                                    
                                       999 Broad Street
                                       Bridgeport, Connecticut 06604
                                       Attention: Alan Aria
                                       Telecopier No.: (203) 382-6573






                 [SIGNATURE PAGE TO FIRST AMENDMENT AGREEMENT]