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                     U.S. SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                     FORM 3

            INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

    Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934,
       Section 17(a) of the Public Utility Holding Company Act of 1935 or
               Section 30(f) of the Investment Company Act of 1940


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1. Name and Address of Reporting Person

     Mullin, Sherman N.
- --------------------------------------------------------------------------------
   (Last)               (First)                 (Middle)

     1611 Ben Lomond Drive
- --------------------------------------------------------------------------------
                                    (Street)
     Glendale, CA  91202

- --------------------------------------------------------------------------------
   (City)               (State)                 (Zip)


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2. Date of Event Requiring Statement (Month/Day/Year)

     1/29/98

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3. IRS or Social Security Number of Reporting Person (Voluntary)


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4. Issuer Name and Ticker or Trading Symbol

     Mercury Computer Systems, Inc.   MRCY
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5 Relationship of Reporting Person to Issuer
   (Check all applicable)

   [ X ]   Director                             [   ]   10% Owner
   [   ]   Officer (give title below)           [   ]   Other (specify below)


              
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6. If Amendment, Date of Original (Month/Year)


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             Table I -- Non-Derivative Securities Beneficially Owned
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                                                                 3. Ownership Form:
                                      2. Amount of Securities       Direct (D) or  
1. Title of Security                     Beneficially Owned         Indirect (I)       4. Nature of Indirect Beneficial Ownership
   (Instr. 4)                            (Instr. 4)                 (Instr. 5)            (Instr.5)                              
- ------------------------------------------------------------------------------------------------------------------------------------
                                                                                 

   Common Stock                          1,250                       D
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Reminder: Report on a separate line for each class of securities beneficially
owned directly or indirectly.

                           (Print or Type Responses)





FORM 3 (continued)

              Table II -- Derivative Securities Beneficially Owned
         (e.g., puts, calls, warrants, options, convertible securities)

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                                                                                                        5. Owner-
                                                    3. Title and Amount of Securities                      ship
                                                       Underlying Derivative Security                      Form of
                         2. Date Exercisable           (Instr. 4)                                          Derivative
                            and Expiration Date     ---------------------------------    4. Conver-        Security:
                            (Month/Day/Year)                               Amount           sion or        Direct      7. Nature of
                         ----------------------                            or               Exercise       (D) or         Indirect
                         Date       Expira-                                Number           Price of       Indirect       Beneficial
1. Title of Security     Exer-      tion                                   of               Derivative     (I)            Ownership
   (Instr. 4)            cisable    Date            Title                  Shares           Security       (Instr.5)      (Instr. 5)
- ------------------------------------------------------------------------------------------------------------------------------------
                                                                                                  
Stock Option             *          7/26/05         Common                 12,000        2.50           D
(right to buy)  
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Stock Option             (1)        7/30/06         Common                 1,812         4.00           D
(right to buy)   
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Stock Option             (2)        9/30/06         Common                 1,811         4.00           D
(right to buy)  
- ------------------------------------------------------------------------------------------------------------------------------------
Stock Option             *          10/20/07        Common                 2,406         8.00           D
(right to buy) 
- ------------------------------------------------------------------------------------------------------------------------------------

====================================================================================================================================

Explanation of Responses:

*    fully exercisable
(1)  25% of this option is exercisable.  The remainder will become exercisable
     in equal increments on July 30 of each of 1998, 1999 and 2000.
(2)  25% of this option is exercisable.  The remainder will become exercisable
     in equal increments on September 30, 1998, 1999 and 2000.


   /s/Sherman M. Mullin                                        1/29/98
- ---------------------------------------------            -----------------------
      **Signature of Reporting Person                             Date

**   Intentional misstatements or omissions of facts constitute Federal Criminal
     Violations.

     See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note:  File three copies of this Form, one of which must be manually signed.
       If space provided is insufficient. See Instruction 6 for procedure.