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                                                                 EXHIBIT 10.11.1

                                                                   Loan No. 1440


                             MODIFICATION AGREEMENT

                                  SECURED LOAN

THIS MODIFICATION AGREEMENT ("Agreement") dated June 1, 2002 is entered into by
and between WELLS FARGO BANK, NATIONAL ASSOCIATION ("Lender"), and
COMMUNICATIONS & POWER INDUSTRIES HOLDING CORPORATION, a Delaware corporation
("Borrower").

                                 R E C I T A L S

A.      Pursuant to the terms of a loan agreement between Borrower and Lender
        dated December 22, 2000 ("Loan Agreement"), Lender made a loan to
        Borrower in the principal amount of EIGHTEEN MILLION AND NO/100 DOLLARS
        ($18,000,000.00) ("Loan"). The Loan is evidenced by a promissory note
        dated as of the date of the Loan Agreement, executed by Borrower in
        favor of Lender, in the principal amount of the Loan ("Note"), and is
        further evidenced by the documents described in the Loan Agreement as
        "Loan Documents". The Note is secured by, among other things, a deed of
        trust ("Deed of Trust") dated December 22, 2000, executed by Borrower,
        as Trustor, to American Securities Company, as Trustee, in favor of
        Lender, as Beneficiary. The Deed of Trust was recorded December 22,
        2000, as Document No. 2000-162764, in the Official Records of San Mateo
        County, California.

B.      As of May 31, 2002, the outstanding principal balance under the Loan was
        Eighteen Million and No/100 Dollars ($18,000,000.00)

C.      The Note, Deed of Trust, Loan Agreement, this Agreement, the other
        documents described in the Loan Agreement as "Loan Documents" (the
        "Existing Loan Documents"), together with all modifications and
        amendments thereto, the Modification Documents (as defined below), and
        any document required hereunder, are collectively referred to
        hereinafter as the "Loan Documents".

D.      By this Agreement, Borrower and Lender intend to modify and amend
        certain terms and provisions of the Loan Documents, which shall become
        effective on June 1, 2002 (the "Effective Date").

NOW, THEREFORE, Borrower and Lender agree as follows:

1.      CONDITIONS PRECEDENT. The following are conditions precedent to Lender's
        obligations under this Agreement:

        1.1     If required by Lender, receipt and approval by Lender of a date
                down to Title Policy No. SM-461651 dated December 22, 2000,
                issued by First American Title Insurance Company ("Title
                Company") and assurance acceptable to Lender, including, without
                limitation, CLTA Endorsement No. 110.5, without deletion or
                exception other than those expressly approved by Lender in
                writing, that the priority and validity of the Deed of Trust
                encumbering the property (the "Property") has not been and will
                not be impaired by this Agreement or the transactions
                contemplated hereby;

        1.2     Receipt by Lender of the executed originals of this Agreement,
                the short form of this Agreement (if any) and any and all other
                documents (the "Modification Documents") and agreements which
                are required by this Agreement or by any other Loan Document,
                each in form and content acceptable to Lender;

        1.3     Recordation in the Official Records of the County where the
                Property is located of (i) the short form of this Agreement (if
                any), and (ii) any other documents which are required to be
                recorded by this Agreement or by any other Loan Document (if
                any);

        1.4     Reimbursement to Lender by Borrower of Lender's costs and
                expenses incurred in connection with this Agreement and the
                transactions contemplated hereby, including, without limitation,
                title insurance costs, recording fees, attorneys' fees,
                appraisal, engineers' and inspection fees and documentation
                costs and charges, whether such services are furnished by
                Lender's employees or agents or by independent contractors;

        1.5     Borrower shall provide, at Borrower's expense, an opinion of
                legal counsel in form and content satisfactory to Lender to the
                effect that: (a) upon due authorization, execution and
                recordation or filing as may be specified in the opinion, each
                of the Modification Documents shall be legal, valid and binding
                instruments, enforceable


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                against the makers thereof in accordance with their respective
                terms; (b) Borrower is duly formed and has all requisite
                authority to enter into the Modification Documents; and (c) such
                other matters, incident to the transactions contemplated hereby,
                as Lender may reasonably request.

        1.6     The representations and warranties contained in this Agreement
                are true and correct;

        1.7     All payments due and owing to Lender under the Loan Documents
                have been paid current as of the effective date of this
                Agreement;

        1.8     Receipt and approval of an updated appraisal of the Property
                satisfactory to Lender;

        1.9     Borrower shall purchase interest rate protection satisfactory to
                Lender in the form of a LIBOR Cap (based on 30-day LIBOR), for
                the notional amount of $17,500,000.00, at a rate not to exceed
                three percent (3.00%) for the six (6) month period beginning
                December 1, 2002 and ending June 1, 2003.

        1.10    The payment to Lender of $250,000.00 to be applied as a
                principal paydown to the Loan. Upon receipt of said principal
                payment, the outstanding principal balance of the Loan shall be
                Seventeen Million Seven Hundred Fifty Thousand and No/100
                Dollars ($17,750,000.00).

        1.11    The payment to Lender of an extension fee in the amount of
                $45,000.00; and

        1.12    The payment to Lender of a documentation fee in the amount of
                $1,000.00.

2.      REPRESENTATIONS AND WARRANTIES. Borrower hereby represents and warrants
        that no Default, breach or failure of condition has occurred, or would
        exist with notice or the lapse of time or both, under any of the Loan
        Documents (as modified by this Agreement) and that all representations
        and warranties herein and in the other Loan Documents are true and
        correct, which representations and warranties shall survive execution of
        this Agreement.

3.      MODIFICATION OF LOAN DOCUMENTS. The Loan Documents are hereby
        supplemented and modified to incorporate the following, which shall
        supersede and prevail over any conflicting provisions of the Loan
        Documents:

        3.1     Extension of Maturity Date. On the Effective Date, the Maturity
                Date recited in the Note is hereby extended to June 1, 2003.

        3.2     Amended and Restated Note. On the Effective Date, the Note
                described in Recital A herein is superseded and replaced in its
                entirety by that certain Amended and Restated Promissory Note
                Secured by Deed of Trust executed by Borrower in the amount of
                SEVENTEEN MILLION SEVEN HUNDRED FIFTY THOUSAND AND NO/100
                DOLLARS ($17,750,000.00) of even date herewith.

        3.3     Principal Payments. In addition to the principal payment
                required in paragraph 1.9 above, Borrower shall make an
                additional principal payment in the amount of TWO HUNDRED FIFTY
                THOUSAND AND NO/100 DOLLARS ($250,000.00) on December 1, 2002.
                Notwithstanding such principal payment, any outstanding
                principal balance under the Note on the Maturity Date shall be
                due and payable on the Maturity Date. Any payment(s) required
                hereunder shall be due and payable on the first day of the month
                in which it is due and shall be applied to the outstanding
                principal balance of the Loan. Any principal balance reductions
                may not be reborrowed.

        3.4     Interest Rate. Except as otherwise provided herein, from and
                after the Effective Date, the Loan shall bear interest (based on
                a 360-day year basis and charged on the basis of actual days
                elapsed) at 4.25% percent per annum above the LIBO Rate pursuant
                to the terms of the Amended and Restated Promissory Note of even
                date herewith.

4.      FORMATION AND ORGANIZATIONAL DOCUMENTS. Borrower has previously
        delivered to Lender all of the relevant formation and organizational
        documents of Borrower, of the partners or joint venturers of Borrower
        (if any), and of all guarantors of the Loan (if any), and all such
        formation documents remain in full force and effect and have not been
        amended or modified since they were delivered to Lender. Borrower hereby
        certifies that: (i) the above


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        documents are all of the relevant formation and organizational documents
        of Borrower; (ii) they remain in full force and effect; and (iii) they
        have not been amended or modified since they were previously delivered
        to Lender.

5.      HAZARDOUS MATERIALS; CCP SECTION 726.5; SECTION 736. Without in any way
        limiting any other provision of this Agreement, Borrower expressly
        reaffirms as of the date hereof, and continuing hereafter: (i) each and
        every representation and warranty in the Loan Documents respecting
        "Hazardous Materials"; and (ii) each and every covenant and indemnity in
        the Loan Documents respecting "Hazardous Materials". In addition,
        Borrower and Lender agree that: (i) this Section is intended as Lender's
        written request for information (and Borrower's response) concerning the
        environmental condition of the real property security under the terms of
        California Code of Civil Procedure Section 726.5; and (ii) each
        representation and/or covenant in this Agreement or any other Loan
        Document (together with any indemnity applicable to a breach of any such
        representation and/or covenant) with respect to the environmental
        condition of the real property security is intended by Lender and
        Borrower to be an "environmental provision" for purposes of California
        Code of Civil Procedure Section 736.

6.      WAIVERS. In further consideration of Lender entering into this
        Agreement, Borrower waives, with respect to the Loan, any and all rights
        to which Borrower is or may be entitled pursuant to Section 580a (the
        so-called "Fair Market Antideficiency Rule"), 580d (the so-called
        "Private Sale Antideficiency Rule") and 726 (the so-called "One Form of
        Action Rule") of the California Code of Civil Procedure, as amended or
        recodified from time to time, together with any other antideficiency or
        similar laws which limit, qualify or reduce Borrower's obligations under
        the Loan Documents.

7.      NON-IMPAIRMENT. Except as expressly provided herein, nothing in this
        Agreement shall alter or affect any provision, condition, or covenant
        contained in the Note or other Loan Document or affect or impair any
        rights, powers, or remedies of Lender, it being the intent of the
        parties hereto that the provisions of the Note and other Loan Documents
        shall continue in full force and effect except as expressly modified
        hereby.

8.      MISCELLANEOUS. This Agreement and the other Loan Documents shall be
        governed by and interpreted in accordance with the laws of the State of
        California, except if preempted by federal law. In any action brought or
        arising out of this Agreement or the Loan Documents, Borrower, and the
        general partners and joint venturers of Borrower, hereby consent to the
        jurisdiction of any federal or state court having proper venue within
        the State of California and also consent to the service of process by
        any means authorized by California or federal law. The headings used in
        this Agreement are for convenience only and shall be disregarded in
        interpreting the substantive provisions of this Agreement. All
        capitalized terms used herein, which are not defined herein, shall have
        the meanings given to them in the other Loan Documents. Time is of the
        essence of each term of the Loan Documents, including this Agreement. If
        any provision of this Agreement or any of the other Loan Documents shall
        be determined by a court of competent jurisdiction to be invalid,
        illegal or unenforceable, that portion shall be deemed severed from this
        Agreement and the remaining parts shall remain in full force as though
        the invalid, illegal, or unenforceable portion had never been a part
        thereof.

9.      INTEGRATION; INTERPRETATION. The Loan Documents, including this
        Agreement, contain or expressly incorporate by reference the entire
        agreement of the parties with respect to the matters contemplated
        therein and supersede all prior negotiations or agreements, written or
        oral. The Loan Documents shall not be modified except by written
        instrument executed by all parties. Any reference to the Loan Documents
        includes any amendments, renewals or extensions now or hereafter
        approved by Lender in writing.


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10.     EXECUTION IN COUNTERPARTS. To facilitate execution, this document may be
        executed in as many counterparts as may be convenient or required. It
        shall not be necessary that the signature of, or on behalf of, each
        party, or that the signature of all persons required to bind any party,
        appear on each counterpart. All counterparts shall collectively
        constitute a single document. It shall not be necessary in making proof
        of this document to produce or account for more than a single
        counterpart containing the respective signatures of, or on behalf of,
        each of the parties hereto. Any signature page to any counterpart may be
        detached from such counterpart without impairing the legal effect of the
        signatures thereon and thereafter attached to another counterpart
        identical thereto except having attached to it additional signature
        pages.

IN WITNESS WHEREOF, Borrower and Lender have caused this Agreement to be duly
executed as of the date first above written.

                                       "LENDER"

                                       WELLS FARGO BANK,
                                       NATIONAL ASSOCIATION

                                       By:
                                               --------------------------------
                                               Jay Rosenberg
                                       Its:    Vice President

                                       "BORROWER"

                                       COMMUNICATIONS & POWER INDUSTRIES
                                       HOLDING CORPORATION,
                                       a Delaware corporation

                                       By:
                                               --------------------------------

                                       Its:
                                               --------------------------------