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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
(RULE 13D-102)
INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO RULES 13D-1(B), (C) AND (D) AND
AMENDMENTS THERETO FILED PURSUANT TO RULE 13D-2(B)
(AMENDMENT NO. __)1
MERCURY COMPUTER SYSTEMS, INC.
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(Name of Issuer)
Common Stock, $0.01 par value per share
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(Title or Class of Securities)
589378-10-8
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(CUSIP Number)
December 31, 1998
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(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
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[X] Rule 13d-1(b)
[_] Rule 13d-1(c)
[_] Rule 13d-1(d)
________________________
1 The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that
section of the Act but shall be subject to all other provisions of the Act
(however, see the Notes).
(Page 1 of 5 Pages)
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CUSIP No. 589378-10-8 13G Page 2 of 5 Pages
_______________________________________________________________________________
1 NAMES OF REPORTING PERSONS
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS
Memorial Drive Trust #04-2272266 Plan #001
_______________________________________________________________________________
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP
(SEE INSTRUCTIONS)
(A)
N/A (B)
_______________________________________________________________________________
3 SEC USE ONLY
_______________________________________________________________________________
4 CITIZENSHIP OF PLACE OR ORGANIZATION
Massachusetts
_______________________________________________________________________________
5 SOLE VOTING POWER
NUMBER OF 2,060,686
SHARES _____________________________________________________________
BENEFICIALLY 6 SHARED VOTING POWER
OWNED BY
EACH 0
REPORTING _____________________________________________________________
PERSON 7 SOLE DISPOSITIVE POWER
WITH
2,060,686
_____________________________________________________________
8 SHARED DISPOSITIVE POWER
0
_______________________________________________________________________________
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
2,060,686
_______________________________________________________________________________
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(SEE INSTRUCTIONS)
N/A
_______________________________________________________________________________
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
20.38%
_______________________________________________________________________________
12 TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
EP
_______________________________________________________________________________
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CUSIP No. 589378-10-8 13G Page 3 of 5 Pages
ITEM 1(A). NAME OF ISSUER:
Mercury Computer Systems, Inc.
ITEM 1(B). ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:
199 Riverneck Road
Chelmsford, MA 01824-2820
ITEM 2(A). NAME OF PERSON FILING:
Memorial Drive Trust ("MDT")
ITEM 2(B). ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE:
125 CambridgePark Drive
6th Floor
Cambridge, MA 02140
ITEM 2(C). PLACE OF ORGANIZATION:
Massachusetts
ITEM 2(D). TITLE OF CLASS OF SECURITIES:
Common Stock, $0.01 par value
ITEM 2(E). CUSIP NUMBER:
589378-10-8
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CUSIP No. 589378-10-8 13G Page 4 of 5 Pages
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ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULES 13D-1(B), OR
13D-2(B), CHECK WHETHER THE PERSON FILING IS A:
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(A) Broker or dealer registered under Section 15 of the Act.
(B) Bank as defined in Section 3(a)(6) of the Act.
(C) Insurance Company as defined in Section 3(a)(19) of the Act.
(D) Investment Company registered under Section 8 of the Investment Company Act.
(E) Investment Adviser registered under Section 203 of the Investment Advisers Act of 1940.
(F) [ ] Employee Benefit Plan, Pension Fund which is subject to the provisions of the Employee
Retirement Income Security Act of 1974 or Endowment Fund; see 13d-1(b)(1)(ii)(F).
(G) Parent Holding Company, in accordance with Rule 13d-1(b) (1)(ii)(G); see Item 7.
(H) Group, in accordance with Rule 13d-1(b)(1)(ii)(H).
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ITEM 4. OWNERSHIP:
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(a) Amount beneficially owned: 2,060,686 shares
(b) Percent of class: 20.38%
(c) Number of shares as to which such person has:
(i) Sole Power to vote or to direct the vote: 2,060,686 shares
(ii) Shared power to vote or to direct the vote: None
(iii) Sole power to dispose or to direct the disposition of: 2,060,686 shares
(iv) Shared power to dispose or to direct the disposition of: None
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ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS:
Not applicable.
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF
ANOTHER PERSON:
Not applicable.
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH
ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT
HOLDING COMPANY:
Not applicable.
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP:
Not applicable.
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CUSIP No. 589378-10-8 13G Page 5 of 5 Pages
ITEM 9. NOTICE OF DISSOLUTION OF GROUP:
Not applicable.
ITEM 10. CERTIFICATION:
By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired in the ordinary
course of business and were not acquired for the purpose of and do not
have the effect of changing or influencing the control of the issuer
of such securities and were not acquired in connection with or as a
participant in any transaction having such purposes or effect.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.
February 9, 1999
---------------------------
(Date)
MEMORIAL DRIVE TRUST
By: /s/ R. Schorr Berman
----------------------
R. Schorr Berman
Administrator and
Chief Executive Officer
