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                                    FORM 8-A

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                     PURSUANT TO SECTION 12(b) OR (g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


                         MERCURY COMPUTER SYSTEMS, INC.
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             (Exact name of registrant as specified in its charter)


             Massachusetts                                     04-2741391
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(State of incorporation or organization)               (I.R.S. Employer ID No.)


                    199 Riverneck Road, Chelmsford, MA 01824
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               (Address of principal executive offices) (Zip Code)


Securities to be registered pursuant to Section 12(b) of the Act:


Title of each class                            Name of each exchange on which
to be so registered                            each class is to be registered
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      N/A

If this Form relates to the registration of a class of debt securities and is
effective upon filing pursuant to General Instruction A(c)(1), please check the
following box. [ ]

If this Form relates to the registration of a class of debt securities and is to
become effective simultaneously with the effectiveness of a concurrent
registration statement under the Securities Act of 1933 pursuant to General
Instructions A(c)(2), please check the following box. [ ]

Securities to be registered pursuant to Section 12(g) of the Act:


                     Common Stock, par value $.01 Per share
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                                (Title of Class)



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Item 1.   Description of Registrant's Securities to be Registered.

     The information set forth in the Section entitled "Description of Capital
Stock" in the Company's Registration Statement on Form S-1 filed with the
Securities and Exchange Commission (File No. 333-41139), as amended, including
any form of the prospectus contained therein filed by the Company pursuant to
Rule 424(b) under the Securities Act of 1933, as amended (the "Registration
Statement"), which is incorporated herein by reference.

Item 2.   Exhibits.

     a.   Specimen Certificate for shares of Common Stock (Incorporated herein
          by reference to Exhibit 4.1 to the Registration Statement).

     b.   Rights of Holders.

          (i)  Restated Articles of Organization, as amended, of Registrant,
               to be effective on or about the effectiveness of the Registration
               Statement (Incorporated herein by reference to Exhibits 3.1 and
               3.3 to the Registration Statement).

          (ii) Amended and Restated By-Laws of Registrant, currently effective
               (Incorporated herein by reference to Exhibit 3.2 to the
               Registration Statement).




                     [Rest of Page Intentionally Left Blank]






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                                   SIGNATURE

     Pursuant to the requirements of Section 12 of the Securities Exchange Act
of 1934, the Registrant has duly caused this Registration Statement to be signed
on its behalf by the undersigned, thereto duly authorized on this 7th day of
January, 1998.

                                         Registrant:
                                         Mercury Computer Systems, Inc.



                                         By: /s/ James R. Bertelli
                                             ---------------------------------
                                             James R. Bertelli
                                             President







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