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Exhibit 10.1

FIFTH AMENDMENT AND WAIVER

    FIFTH AMENDMENT AND WAIVER (this "Amendment"), dated as of September 28,
2001, among ELGAR HOLDINGS, INC. ("Holdings"), ELGAR ELECTRONICS CORPORATION
(the "Borrower"), the lenders party to the Credit Agreement referred to below
(the "Banks"), and BANKERS TRUST COMPANY, as Agent (in such capacity, the
"Agent"). All capitalized terms used herein and not otherwise defined herein
shall have the respective meanings provided such terms in the Credit Agreement
referred to below.

W  I  T  N  E  S  S  E  T  H:

    WHEREAS, Holdings, the Borrower, the Banks and the Agent are parties to a
Credit Agreement, dated as of February 3, 1998, and amended and restated as of
May 29, 1998 (as amended, modified or supplemented to, but not including, the
date hereof, the "Credit Agreement");

    WHEREAS, the parties hereto wish to amend/or waive certain provisions of the
Credit Agreement as herein provided; and

    WHEREAS, subject to the terms and conditions of this Amendment, the parties
hereto agree as follows:

    NOW, THEREFORE, it is agreed:

    1.  Section 4.02(b) of the Credit Agreement is hereby amended by deleting
the text "September 30, 2001" set forth opposite the Scheduled Payment amount of
"$1,000,000" appearing in the table therein and inserting the text "October 5,
2001" in lieu thereof.

    2.  This Amendment shall become effective on the date (the "Amendment
Effective Date") when each of Holdings, the Borrower and the Required Banks
shall have signed a counterpart hereof (whether the same or different
counterparts) and shall have delivered (including by way of facsimile
transmission) the same to the Agent at the Notice Office.

    3.  This Amendment may be executed in any number of counterparts and by the
different parties hereto on separate counterparts, each of which counterparts
when executed and delivered shall be an original, but all of which shall
together constitute one and the same instrument. A complete set of counterparts
shall be delivered to Holdings, the Borrower and the Agent.

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

    5.  From and after the Amendment Effective Date, all references in the
Credit Agreement and each of the other Credit Documents to the Credit Agreement
shall be deemed to be references to the Credit Agreement as modified hereby.

    6.  This Amendment is limited as specified and shall not constitute a
modification, acceptance or waiver of any other provision of the Credit
Agreement or any other Credit Document.

* * *

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    IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart of
this Amendment to be duly executed and delivered as of the date first above
written.

    ELGAR HOLDINGS, INC.
 
 
By:
 
/s/ Kenneth R. Kilpatrick

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Title: President and Chief Executive Officer
 
 
ELGAR ELECTRONICS CORPORATION
 
 
By:
 
/s/ Kenneth R. Kilpatrick

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Title: President and Chief Executive Officer
 
 
BANKERS TRUST COMPANY,
Individually and as Agent
 
 
By:
 
/s/ Patrick W. Dowling

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Title: Vice President

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Exhibit 10.1
FIFTH AMENDMENT AND WAIVER