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                                                                    EXHIBIT 10.2


                          AMENDMENT TO CREDIT AGREEMENT

         THIS AMENDMENT ("Amendment") made as of February 17, 1998, between ECC
INTERNATIONAL CORP. ("ECC"), ECC SIMULATION LIMITED ("Simulation") and FIRST
UNION NATIONAL BANK (successor by merger to First Fidelity Bank, National
Association) ("Bank").

                                   BACKGROUND

         Bank and ECC entered into a certain Term Loan and Revolving Credit
Agreement dated as of September 20, 1994 (as amended to date, the "ECC Credit
Agreement") relative to, inter alia, a Revolver (the "ECC Revolver"), as more
fully set forth therein, the terms of which are incorporated herein by
reference. Bank and Simulation entered into a certain Revolving Credit Agreement
dated as of September 20, 1994 (as amended to date, the "Simulation Credit
Agreement") relative to a Revolver (the "Simulation Revolver"), as more fully
set forth therein, the terms of which are incorporated herein by reference. The
parties desire to amend the ECC Credit Agreement and the Simulation Credit
Agreement and provide certain waivers in the manner hereinafter provided. All
capitalized terms used herein which are not defined hereby shall have the
meaning ascribed thereto in the ECC Credit Agreement. Subject to the
satisfaction of all conditions specified herein, all amendments and other
matters effected hereby are, unless otherwise stated herein to the contrary,
effective as of the date hereof.

         NOW, THEREFORE, the parties, INTENDING TO BE LEGALLY BOUND, agree as
follows:

         1.   Loans to Simulation. Effective as of February 13, 1998, the
reference in Section P.1 of the ECC Credit Agreement and in Section N.1 of the
Simulation Credit Agreement to "$1,500,000" (representing the amount that ECC
may lend to Simulation) is hereby replaced by "$3,000,000".

         2.   Fixed Charge Covenant.

              a.   Borrowers have advised Bank that Borrowers have failed to
comply with the Fixed Charge Ratio for the fiscal period ending December 31,
1997. Bank hereby irrevocably waives said noncompliance as of December 31, 1997.
Such waiver relates only to the specific covenant and for the fiscal period set
forth above, and shall in no event imply any obligation of Bank to grant any
other or further waiver.

              b.   Effective as of January 1, 1998, Section P.13 of the ECC
Credit Agreement and Section N.13 of the Simulation Credit Agreement are hereby
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amended and restated in their entirety to read as follows:

              "Fixed Charge Covenant. Permit the Fixed Charge Ratio to be less
              than 1.25 to 1.0 as of 3/31/98 and 2.25 to 1.0 as of 6/30/98 and
              as of 9/30/98. As used herein, "Fixed Charge Ratio" means, as of
              any date, the ratio of (i) Consolidated net income plus
              depreciation, interest expense and taxes for the fiscal quarter
              ending on such date, to (ii) Fixed Charges of the Borrower and all
              Consolidated Persons for such fiscal quarter, and "Fixed Charges"
              means the sum of dividends, payments on capital leases, interest
              expense and principal payments ("Principal on Long Term Debt") on
              indebtedness for borrowed money which matures more than one year
              from the date of such principal payment."

         3.   Current Ratio. Effective as of 12/31/97, the outstanding principal
balance of the ECC Revolver and the Simulation Revolver shall not be included as
a Current Liability for purposes of calculating the Consolidated Current Ratio.

         4.   Maximum Principal Amount of ECC Revolver and Simulation Revolver.

              a.   Effective the date hereof, and notwithstanding Section A.2.b.
of the ECC Credit Agreement to the contrary, the maximum aggregate principal
amount of advances, including the face amount of Letters of Credit (as defined
in the ECC Credit Agreement), to be outstanding at any time under the ECC
Revolver (the "Maximum Principal Amount") shall be an amount which, when taken
together with the principal amount of cash advances and the face amount of
letters of credit outstanding under the Simulation Revolver, is not greater than
$13,000,000.

              b.   Effective the date hereof, and notwithstanding Section A.1.b.
of the Simulation Credit Agreement to the contrary, the Maximum Principal Amount
(as defined in the Simulation Credit Agreement) of advances, including the face
amount of letters of credit, to be outstanding at any time under the Simulation
Revolver shall be an amount which is equal to the lesser of (i) $5,500,000 or
(ii) an amount which, when taken together with the principal amount of cash
advances and the face amount of letters of credit outstanding under the ECC
Revolver, is not greater than $13,000,000; provided, that notwithstanding the
foregoing to the contrary, if due solely to fluctuations in the exchange rate
for Dollars and Pounds Sterling, the Equivalent Dollar Amount (as defined in the
Simulation Credit Agreement) of outstanding cash advances and the face amount of
outstanding letters of credit made in Pounds Sterling, when taken together with
outstanding cash advances and the face amount of outstanding letters of credit
made in Dollars under the Simulation Credit Agreement, exceeds the applicable
sublimit set forth in subpart (i) above by 10% or less, Simulation need not
repay such excess until the Expiration Date, provided, that if the same exceeds
the said applicable sublimit by more than 10% or if the


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Equivalent Dollar Amount of outstanding cash advances and the face amount of
outstanding letters of credit made in Pounds Sterling, when taken together with
the sum of outstanding cash advances and the face amount of outstanding letters
of credit made in Dollars and the principal amount of cash advances and the face
amount of letters of credit outstanding under the ECC Revolver, exceeds
$13,000,000, Simulation will repay the principal of the Simulation Revolver in
the amount of such excess within one (1) Business Day after notice thereof from
Bank.

         5.   Applicable Margin. Section D.2. of the ECC Credit Agreement and
Section C.2. of the Simulation Credit Agreement are hereby amended in order
that, effective as of the date hereof and thereafter until all Liabilities under
each Credit Agreement are repaid in full, but subject in all events to the
Bank's right to charge interest at the Default Rate (as defined in the
applicable Revolving Credit Note), the Applicable Margin for principal
outstanding under the ECC Revolver and the Simulation Revolver which accrues
interest tied to the Eurodollar Rate is plus 2.25 percentage points.

         6.   Conditions. The effectiveness of the amendments, waiver and other
provisions hereof is subject to satisfaction of the following conditions
precedent:

              a.   ECC shall, concurrently herewith, execute and deliver to Bank
an amended and restated Revolving Credit Note in the face amount of $13,000,000,
which amended and restated Revolving Credit Note, together with any attachments
thereto and amendments, modifications or restatements thereof or thereto, shall
constitute the "Revolving Credit Note" for all purposes of the ECC Credit
Agreement and related Loan Documents;

              b.   Simulation shall, concurrently herewith, execute and deliver
to Bank an amended and restated Revolving Credit Note in the face amount of
$5,500,000, which amended and restated Revolving Credit Note, together with any
attachments thereto and amendments, modifications or restatements thereof or
thereto, shall constitute the "Revolving Credit Note" for all purposes of the
Simulation Credit Agreement and related Loan Documents;

              c.   ECC shall, concurrently herewith, pay to Bank an amendment
fee in the amount of $15,000;

              d.   ECC and Simulation shall, concurrently herewith, deliver to
Bank certified resolutions of its Board of Directors authorizing it to execute,
deliver and perform this Amendment and any documents required to be executed in
connection herewith;

              e.   Each of ECC and Simulation shall deliver to Bank such other
documents, instruments and agreements as Bank may reasonably request.


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         7.   Representations and Warranties. ECC and Simulation each represents
and warrants to Bank that:

              a.   The execution and delivery by ECC and Simulation of this
Amendment and the performance by it of the transactions herein contemplated (i)
are and will be within its powers; (ii) have been authorized by all necessary
corporate action; and (iii) are not and will not be in contravention of any
order of any court or other agency of government, of law or any other indenture,
agreement or undertaking to which ECC or Simulation is a party or by which the
property of ECC or Simulation is bound, or be in conflict with, result in a
breach of constitute (with due notice and/or lapse of time) a default under any
such indenture, agreement or undertaking or result in the imposition of any
lien, charge or incumbrance of any nature on any of the properties of ECC or
Simulation.

              b.   This Amendment is valid, legal, binding and enforceable in
accordance with its terms.

              c.   No Default or Event of Default, other than that which is
expressly being waived pursuant to the terms hereof, is outstanding.

         8.   Reaffirmation. Except as specifically modified by this Amendment,
the ECC Credit Agreement and the Simulation Credit Agreement and all other Loan
Documents referred to in either thereof shall remain unchanged and in full force
and effect, and this Amendment shall be construed as supplemental thereto, and
each of ECC and Simulation hereby reaffirms all of its Liabilities thereunder
and agrees that the same are owing to Bank in accordance with the terms thereof
without off-set, counterclaim or defense of any nature. Each of ECC and
Simulation further reaffirms all guaranties, liens and security interests
heretofore granted by it to Bank pursuant to the Loan Documents, including
without limitation the liens, security interests and guaranties granted pursuant
to the Security Agreement dated September 20, 1994, among Bank, ECC, ECC
International, Inc. and Educational Computer Corporation International
("Security Agreement"), that certain Guarantee and Debenture dated September 20,
1994, executed and delivered by Simulation to Bank ("Guaranty and Debenture"),
that certain Guaranty and Surety Agreement dated September 20, 1994, from ECC,
ECC International, Inc. and Educational Computer Corporation to Bank
("Guaranty") and that certain Mortgage, Assignment of Rents and Security
Agreement dated April 6, 1995 from ECC to Bank ("Mortgage").

         9.   Counterpart. This Amendment may be executed in any number of
counterparts, each of which shall constitute an original and all of which, taken
together, shall constitute one and the same instrument.


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         IN WITNESS WHEREOF, the parties have executed this Amendment as of the
date first above written.


Attest:                                     ECC INTERNATIONAL CORP.


By:  /s/ Relland Winand                     By:  /s/ George W. Murphy
   ------------------------------              ------------------------------
    Name:  Relland Winand                       Name:  George W. Murphy
    Title: Vice President, Finance              Title: President


Attest:                                     ECC SIMULATION LIMITED


By:  /s/ Relland Winand                     By:  /s/ George W. Murphy
   ------------------------------              ------------------------------
    Name:  Relland Winand                      Name:  George W. Murphy
    Title: Vice President, Finance             Title: President


                                            FIRST UNION NATIONAL BANK


                                            By:  /s/ Stephanie Micua
                                               ------------------------------
                                                Name:  Stephanie Micua
                                                Title: Asst. Vice President


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                                     JOINDER

         Each of the undersigned consents to the foregoing Amendment, the terms
of which are incorporated herein by reference.

         IN WITNESS WHEREOF, the undersigned have executed this Joinder this
17th day of February, 1998.


Attest:                                     ECC INTERNATIONAL CORP.


By:  /s/ Relland Winand                     By:  /s/ George W. Murphy
   ------------------------------              ------------------------------
    Name:  Relland Winand                      Name:  George W. Murphy
    Title: Secretary/Treasurer                 Title: President


Attest:                                     EDUCATIONAL COMPUTER
                                            CORPORATION INTERNATIONAL


By:  /s/ Relland Winand                     By:  /s/ George W. Murphy
   ------------------------------              ------------------------------
    Name:  Relland Winand                       Name:  George W. Murphy
    Title: Secretary/Treasurer                  Title: President


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