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                                                                   EXHIBIT 10.13

                                                                   Loan No. 1440


                          SECOND MODIFICATION AGREEMENT
                                  SECURED LOAN

THIS SECOND MODIFICATION AGREEMENT ("Agreement") dated May 30, 2003 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/100THS 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.    The Note, Deed of Trust and Loan Agreement have been previously amended
      and modified by modification agreements dated: June 1, 2002 (the "First
      Modification").

C.    The outstanding principal balance under the Loan as of the date hereof is
      SEVENTEEN MILLION FIVE HUNDRED THOUSAND AND NO/100THS ($17,500,000.00).

D.    The Note, Deed of Trust, Loan Agreement, this Agreement, the other
      documents described in the Loan Agreement as "Loan Documents", together
      with all modifications and amendments thereto and any document required
      hereunder, are collectively referred to herein as the "Loan Documents".

E.    By this Agreement, Borrower and Lender intend to modify and amend certain
      terms and provisions of the Loan Documents.

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


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

      1.7   The payment to Lender of an extension fee in the amount of
            $43,750.00; and

      1.8   The payment to Lender of a documentation fee in the amount of
            $500.00.

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. Effective as of June 1, 2003, the
            Maturity Date recited in the Note, as amended, is hereby extended to
            January 31, 2004.

      3.2   INTEREST. Except as otherwise provided in this Agreement, the
            interest rate recited and calculated in the manner provided for in
            the Note and Loan Documents shall remain unchanged. Borrower shall
            continue to pay interest at the time and place and in the manner
            provided in the Note and Loan Documents, as amended by this
            Agreement.

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 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


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      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.

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:  _____________________________________


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               JUNIOR LIENOR'S CONSENT AND SUBORDINATION AGREEMENT

      NOTICE: THIS JUNIOR LIENOR CONSENT AND SUBORDINATION AGREEMENT RESULTS IN
      YOUR SECURITY INTEREST IN THE PROPERTY REMAINING SUBJECT TO AND OF A LOWER
      PRIORITY THAN THE LIEN OF THE DEED OF TRUST AS MODIFIED BY THE FOREGOING
      SECOND MODIFICATION AGREEMENT.

The undersigned ("Junior Lienor"), as owner and holder of a security interest
("Junior Security Interest") evidenced by that certain unrecorded Lease, which
is junior, subordinate and subject to the terms, covenants, conditions and
restrictions of the Deed of Trust, as modified by the foregoing Modification
Agreement, hereby acknowledges its consent to the terms and provisions of the
foregoing Second Modification Agreement and the transactions contemplated
thereby. The undersigned further reaffirms the full force and effectiveness of
that certain Subordination Agreement, dated December 22, 2000, between the
undersigned and Communications & Power Industries Holding Corporation, a
Delaware corporation and acknowledges that the Junior Security Interest is
junior, subordinate and subject to the Deed of Trust, as modified by the
foregoing Second Modification Agreement.

      NOTICE: THE LOAN DOCUMENTS MAY CONTAIN A PROVISION WHICH MAY ALLOW THE
      PERSON OBLIGATED ON YOUR REAL PROPERTY SECURITY TO EXPEND A PORTION OF THE
      LOAN FOR OTHER PURPOSES THAN IMPROVEMENT OF THE PROPERTY.

Agreed and Acknowledged:

Dated as of:  May 30, 2003                           "JUNIOR LIENOR"

                                     COMMUNICATIONS & POWER INDUSTRIES, INC.,
                                     a Delaware corporation

                                     By:   _____________________________________

                                     Its:  _____________________________________


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                         HAZARDOUS INDEMNITOR'S CONSENT

The undersigned ("Indemnitor") consents to the foregoing Second Modification
Agreement and the transactions contemplated thereby and reaffirms its
obligations under the Unsecured Hazardous Materials Indemnity Agreement
("Indemnity") dated December 22, 2000, and its waivers, as set forth in the
Indemnity, of each and every one of the possible defenses to such obligations.
Indemnitor further reaffirms that its obligations under the Indemnity are
separate and distinct from Borrower's obligations.

Indemnitor, as indemnitor under the Indemnity, understands that the Lender's
exercise of a non-judicial foreclosure sale under the subject Deed of Trust
will, by virtue of California Code of Civil Procedure Section 580d, result in
the destruction of any subrogation, reimbursement or contribution rights which
Indemnitor, as indemnitor under the Indemnity, may have against the Borrower.
Indemnitor, as indemnitor under the Indemnity, further understands that such
exercise by Lender and the consequent destruction of subrogation, reimbursement
or contribution rights would constitute a defense to the enforcement of the
Indemnity by Lender. With this explicit understanding, Indemnitor, as indemnitor
under the Indemnity, nevertheless specifically waives any and all rights and
defenses arising out of an election of remedies by Lender, even though that
election of remedies, such as a nonjudicial foreclosure with respect to security
for a guaranteed obligation, has destroyed Indemnitor's, as indemnitor under the
Indemnity, rights of subrogation and reimbursement against the principal by the
operation of Section 580d of the California Code of Civil Procedure or
otherwise. Indemnitor, as indemnitor under the Indemnity, further specifically
waives any and all rights and defenses that Indemnitor, as indemnitor under the
Indemnity, may have because Borrower's debt is secured by real property; this
means, among other things, that: (1) Lender may collect from Indemnitor, as
indemnitor under the Indemnity, without first foreclosing on any real or
personal property collateral pledged by Borrower; (2) if Lender forecloses on
any real property collateral pledged by Borrower, then (A) the amount of the
debt may be reduced only by the price for which that collateral is sold at the
foreclosure sale, even if the collateral is worth more than the sale price, and
(B) Lender may collect from Indemnitor, as indemnitor under the Indemnity, even
if Lender, by foreclosing on the real property collateral, has destroyed any
right Indemnitor, as indemnitor under the Indemnity, may have to collect from
Borrower. The foregoing sentence is an unconditional and irrevocable waiver of
any rights and defenses Indemnitor, as indemnitor under the Indemnity, may have
because Borrower's debt is secured by real property. These rights and defenses
being waived by Indemnitor, as indemnitor under the Indemnity, include, but are
not limited to, any rights or defenses based upon Section 580a, 580d or 726 of
the California Code of Civil Procedure. This understanding and waiver is made in
addition to and not in limitation of any of the existing terms and conditions of
the Indemnity.

AGREED:

Dated as of:  May 30, 2003                           "INDEMNITOR"

                                     COMMUNICATIONS & POWER INDUSTRIES HOLDING
                                     CORPORATION, a Delaware corporation

                                     By:    ____________________________________
                                     Name:  ____________________________________
                                     Its:   ____________________________________


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