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                                                                     EXHIBIT 4.9

                          AMENDMENT TO RIGHTS AGREEMENT

        This Amendment to Rights Agreement ("Amendment") is made and entered
into as of November 6, 1998, by and between California Microwave, Inc., a
Delaware corporation (the "Company"), and BankBoston, N.A. (successor to Bank of
America, N.T. & S.A.) (the "Rights Agent").

                                   WITNESSETH

        WHEREAS, the Company has entered into a Rights Agreement, dated as of
July 27, 1989, with Bank of America, N.T. & S.A. (the "Agreement") pursuant to
which Board of Directors of the Company authorized and declared a dividend of
one Right for each share of the Company's Common Stock outstanding at the close
of business on the Record Date and authorized and directed the issuance of one
Right with respect to each share of Common Stock that shall become outstanding
between the Record Date and the earlier of the Distribution Date, the Expiration
Date and the Final Expiration Date, each Right representing the right to
purchase one share of Common Stock on the terms and subject to the conditions
set forth therein.

        WHEREAS, the Board of Directors of the Company deems it desirable and in
the best interests of stockholders to amend the Agreement as set forth herein.

        NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein set forth, the parties hereby agree as follows:

        SECTION 1. CERTAIN DEFINITIONS. For purposes of this Amendment,
capitalized terms not otherwise defined herein shall have the meanings indicated
in the Agreement.

        SECTION 2.    AMENDMENT.

        (A) Section 1(a) is amended and restated in its entirety as follows:

               (a) "Acquiring Person" shall mean any Person (as such term is
        hereafter defined) who or which, together with all Affiliates and
        Associates (as such terms are hereafter defined) of such Person, shall
        be the Beneficial Owner (as such term is hereafter defined) of 20% or
        more of the Common Stock of the Company then outstanding.
        Notwithstanding the foregoing, (A) the term "Acquiring Person" shall not
        include (i) the Company, (ii) any subsidiary (as such term is hereafter
        defined) of the Company, (iii) any employee benefit plan of the Company
        or of any subsidiary of the Company, (iv) any entity holding Common
        Stock for or pursuant to the terms of any such employee benefit plan, or
        (v) any Person who or which has received the approval of the Board of
        Directors (together with the Approval of the Continuing Directors) (as
        such term is hereafter defined) of the Company to become the Beneficial
        Owner of 20% or more of the Common Stock, which approvals may be before
        or within twenty (20) Business Days after the Person becomes the
        Beneficial Owner of 20% or more of the Common Stock then outstanding,
        and (B) no Person shall become an "Acquiring Person" either (x) as the
        result of an acquisition of Common Stock by the Company which, by
        reducing the number of shares outstanding, 



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        increases the proportionate number of shares beneficially owned by such
        Person to 20% or more of the Common Shares then outstanding; provided,
        however, that if a Person shall become the Beneficial Owner of 20% or
        more of the Common Stock then outstanding by reason of share purchases
        by the Company and shall, following written notice from, or public
        disclosure by, the Company of such share purchases by the Company,
        become the Beneficial Owner of any additional Common Stock without the
        prior consent of the Company and shall then Beneficially Own more than
        3,000,000 shares of the Common Stock (subject to adjustment for stock
        splits, stock combinations, recapitalizations, reclassifications and the
        like), then such Person shall be deemed to be an "Acquiring Person," or
        (y) if the Board of Directors determines in good faith that a Person who
        would otherwise be an "Acquiring Person," as defined pursuant to the
        foregoing provisions of this paragraph (a), has become such
        inadvertently, and such Person divests, as promptly as practicable (as
        determined in good faith by the Board of Directors), but in any event
        within five Business Days, following receipt of written notice from the
        Company of such event, of Beneficial Ownership of a sufficient number of
        shares of Common Stock so that such Person would no longer be an
        Acquiring Person, as defined pursuant to the foregoing provisions of
        this paragraph (a), then such Person shall no longer be deemed to be an
        "Acquiring Person" for purposes of this Agreement.

        (b)    Section 1(f) shall be amended to change the words "State of
               California" to "Commonwealth of Massachusetts".

        (c)    Section 1(i) shall be amended to change the words "San Francisco"
               to "Eastern" where they appear twice.

        (d)    Section 2 shall be amended to add the following after the words
               "necessary or desirable":

        upon ten (10) days prior written notice to the Rights Agent. The Rights
        Agent shall have no duty to supervise, and shall in no event be liable
        for, the acts or omissions of any such co-Rights Agent.

        (e)     The following shall be added as a new paragraph at the end of
                Section 7(a):

               In lieu of issuing Common Stock in accordance with the first
        paragraph of Section 7(a) hereof, the Company may, if a majority of the
        Board of Directors then in office determines that such action is
        necessary or appropriate and not contrary to the interests of holders of
        Rights, elect to (and, in the event that there are not sufficient
        treasury shares and authorized but unissued Common Stock to permit the
        exercise in full of the Rights in accordance with the foregoing
        paragraph, the Company shall) take all such action as may be necessary
        to authorize, issue or pay, upon the exercise of the Rights, cash
        (including by way of a reduction of the Purchase Price), property,
        Preferred Stock, other securities or any combination thereof having an
        aggregate value equal to the value of the Common Stock which otherwise
        would have been issuable pursuant to the first paragraph of Section 7(a)
        hereof, which aggregate value shall be determined by a nationally
        recognized investment banking firm selected by a majority of the Board
        of Directors then in office. For purposes of the preceding sentence, the
        value of the Common Stock shall be determined pursuant to 



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        Section 11(d) hereof. Any such election by the Board of Directors must
        be made within 60 days following the Distribution Date. Following the
        Distribution Date, a majority of the Board of Directors then in office
        may suspend the exercisability of the Rights for a period of up to 60
        days following the Distribution Date to the extent that such directors
        have not determined whether to exercise their rights of election under
        this paragraph Section 7(a). In the event of any such suspension, the
        Company shall issue a public announcement stating that the
        exercisability of the Rights has been temporarily suspended.

        (f)    Section 7(b) shall be amended to add the following after the
               words "Common Stock":

        (or cash, property, Preferred Stock, other securities or combination
        thereof substituted therefor in accordance with the second paragraph of
        Section 7(a)).

        (g)     Section 7(c) is hereby amended and restated in its entirety as
                follows:

               (c) Subject to the second paragraph of Section 7(a), upon receipt
        of a Right Certificate representing exercisable Rights, with the form of
        election to purchase set forth on the reverse thereof (or a facsimile
        thereof) and the Certificate contained therein duly executed,
        accompanied by payment of the Purchase Price for the shares of Common
        Stock (or cash, property, Preferred Stock, other securities or any
        combination thereof substituted therefor in accordance with the second
        paragraph of Section 7(a)) to be purchased and an amount equal to any
        applicable transfer tax in cash, or by certified check or bank draft
        payable to the order of the Company, the Rights Agent shall thereupon
        promptly (i) requisition from any transfer agent of the Common Stock (or
        make available, if the Rights Agent is the transfer agent) certificates
        for the number of shares of Common Stock (or, when appropriate, from the
        Company cash, property, Preferred Stock, other securities or any
        combination thereof) to be purchased and the Company hereby irrevocably
        authorizes and directs its transfer agent to comply with all such
        requests, (ii) when appropriate, requisition from the Company the amount
        of cash to be paid in lieu of issuance of fractional shares in
        accordance with Section 14, (iii) promptly after receipt of such Common
        Stock certificates or other cash, property, Preferred Stock, other
        securities or any combination thereof substituted therefor in accordance
        with the second paragraph of Section 7(a), cause the same to be
        delivered to or upon the order of the registered holder of such Right
        Certificate, registered in such name or names as may be designated by
        such holder and (iv) when appropriate, after receipt, promptly deliver
        such cash to or upon the order of the registered holder of such Right
        Certificate. Notwithstanding the foregoing provisions of this Section
        7(c), the Company may suspend the issuance of shares of Common Stock
        upon exercise of a Right for a reasonable period, not in excess of 90
        days, during which the Company seeks to register under the Securities
        Act of 1933, as amended, and any applicable securities law of any other
        jurisdiction the shares of Common Stock or other securities to be issued
        pursuant to the Rights.

        (h) Section 9 is hereby amended and restated in its entirety as follows:

               Section 9. Listing and Issuance of Common Stock. Subject to the
        second paragraph of Section 7(a), so long as the Common Stock issuable
        upon the exercise of 



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        Rights may be listed on any national securities exchange, the Company
        shall use its best efforts to cause, from and after such time as the
        Rights become exercisable, all shares of Common Stock to be issued on
        such exchange upon official notice of issuance upon such exercise. The
        Company covenants and agrees that it will take all such action as may be
        necessary to ensure that all shares of Common Stock delivered upon
        exercise of Rights shall, at the time of delivery of the certificates
        for such Common Stock (subject to payment of the Purchase Price), be
        duly and validly authorized and issued and fully paid and nonassessable
        shares. The Company further covenants and agrees that it will pay when
        due and payable any and all federal and state transfer taxes and charges
        which may be payable in respect of the issuance or delivery of the Right
        Certificates or of any Common Stock issued upon the exercise of Rights.
        The Company shall not, however, be required to pay any transfer tax
        which may be payable in respect of any transfer or delivery of Right
        Certificates to a person other than, or the issuance or delivery of
        certificates for the Common Stock in a name other than that of, the
        registered holder of the Right Certificate evidencing Rights surrendered
        for exercise or to issue or deliver any certificates for Common Stock
        upon the exercise of any Rights until any such tax shall have been paid
        (any such tax being payable by the holder of such Right Certificate at
        the time of surrender) or until it has been established to the Company's
        satisfaction that no such tax is due.

        (i)    Section 18 and Section 20(c) shall be amended to add the word
               "gross" before the words "negligence, bad faith or willful
               misconduct".

        (j)    Section 25 shall be amended to replace the address of the Rights
               Agent with the following:

        BankBoston, N.A.
        c/o Boston EquiServe Limited Partnership
        150 Royall Street
        Canton, MA 02021
        Attn:  Client Administration

        SECTION 3. GOVERNING LAW. This Amendment, the Agreement and each Right
Certificate issued thereunder shall be deemed to be a contract made under the
laws of the State in which the Company or its successor is incorporated and for
all purposes shall be governed by and construed in accordance with the laws of
such State applicable to contracts to be made and performed entirely within such
State.

        SECTION 4. COUNTERPARTS. This Amendment may be executed in any number of
counterparts and each of such counterparts shall for all purposes be deemed to
be an original, and all such counterparts shall together constitute but one and
the same instrument.

        SECTION 5. BENEFITS OF THIS AGREEMENT. Nothing in this Amendment shall
be construed to give any Person other than the Company, the Rights Agent and the
registered holders of the Right Certificates (and, prior to the Distribution
Date, registered holders of the Common Stock) any legal or equitable right,
remedy, or claim under this Amendment or the Agreement; but this Amendment and
the Agreement shall be for the sole and exclusive benefit of the Company, the



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Rights Agent and the registered holders of the Right Certificates (and, prior to
the Distribution Date, registered holders of the Common Stock).

        SECTION 6. DESCRIPTIVE HEADINGS. Descriptive headings of the several
Sections of this Amendment are inserted for convenience only and shall not
control or affect the meaning or construction of any of the provisions hereof.

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and their respective corporate seals to be hereunto affixed and
attested, all as of the day and year first above written.

                                       CALIFORNIA MICROWAVE, INC.

Attest:

By:     /s/ Kenneth J. Wees            By:    /s/ Donna S. Birks
   --------------------------------       --------------------------------------
        Title: VP, General Counsel &           Title:  EVP & CFO
                  Secretary

Attest:                                BANKBOSTON, N.A.
                                       (Successor to Bank of America, 
                                       N.T. & S.A.)

By:     /s/ Ingrid Freire              By:    /s/ Geoffrey D. Anderson
   --------------------------------       --------------------------------------
        Title:  Account Manager               Title:  Director





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