<PAGE>
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. 2 )*
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Giga-Tronics Inc.
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(Name of Issuer)
COMMON STOCK
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(Title of Class of Securities)
375175106
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(CUSIP Number)
Check the following box if a fee is being paid with this statement / /. (A
fee is not required only if the filing person: (1) has a previous statement
on file reporting beneficial ownership of more than five percent of the class
of securities described in Item 1; and (2) has filed no amendment subsequent
thereto reporting beneficial ownership of five percent or less of such
class.) (See Rule 13d-7).
*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 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. 375175106 13G Page 2 of 8
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(1) Name of Reporting Person S.S. or I.R.S. Identification No. of Above
Person
MONTGOMERY ASSET MANAGEMENT, LLC 94-3273703
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(2) Check the Appropriate Box if a Member (a) / /
of a Group* (b) / /
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(3) SEC Use Only
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(4) Citizenship or Place of Organization
DELAWARE
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Number of Shares (5) Sole Voting Power
Beneficially 143,000 (as of 12/31/97)
Owned by --------------------------------------------------
Each Reporting (6) Shared Voting Power
Person With -0-
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(7) Sole Dispositive Power
143,000 (as of 12/31/97)
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(8) Shared Dispositive Power
-0-
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(9) Aggregate Amount Beneficially Owned by Each Reporting Person
143,000 (as of 12/31/97)
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(10) Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares*
Not applicable
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(11) Percent of Class Represented by Amount in Row (9)
3.31% (as of 12/31/97)
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(12) Type of Reporting Person*
IA
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*SEE INSTRUCTIONS
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CUSIP No. 375175106 13G Page 3 of 8
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(1) Name of Reporting Person S.S. or I.R.S. Identification No. of Above
Person
Montgomery Micro Cap Fund 94-3215737
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(2) Check the Appropriate Box if a Member (a) / /
of a Group* (b) / /
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(3) SEC Use Only
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(4) Citizenship or Place of Organization
Massachusetts
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Number of Shares (5) Sole Voting Power
Beneficially 143,000 (as of 12/31/97)
Owned by --------------------------------------------------
Each Reporting (6) Shared Voting Power
Person With -0-
--------------------------------------------------
(7) Sole Dispositive Power
143,000 (as of 12/31/97)
--------------------------------------------------
(8) Shared Dispositive Power
-0-
- -------------------------------------------------------------------------------
(9) Aggregate Amount Beneficially Owned by Each Reporting Person
143,000 (as of 12/31/97)
- -------------------------------------------------------------------------------
(10) Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares*
Not applicable
- -------------------------------------------------------------------------------
(11) Percent of Class Represented by Amount in Row (9)
3.31% (as of 12/31/97)
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(12) Type of Reporting Person*
IV
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*SEE INSTRUCTIONS
<PAGE>
Page 4 of 8
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ITEM 1
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(a). NAME OF ISSUER
Giga-Tronics Inc.
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(b). ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES
4650 Norris Canyon Rd., San Ramon, CA 94583
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ITEM 2
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(a). NAME OF PERSON(S) FILING
MONTGOMERY ASSET MANAGEMENT, LLC
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(b). ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE
101 CALIFORNIA STREET, SAN FRANCISCO, CA 94111
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(c). CITIZENSHIP
DELAWARE LIMITED LIABILITY COMPANY
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(d). TITLE OF CLASS OF SECURITIES
Common Stock
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(e). CUSIP NUMBER
375175106
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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
(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) /x/ 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 Section 240.13d-1(b)(1)(ii)(F)
(g) / / Parent Holding Company, in accordance with Section
240.13d-1(b)(ii)(G) (Note: See Item 7)
(h) / / Group, in accordance with Section 240.13d-1(b)(1)(ii)(H)
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Page 5 of 8
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ITEM 4. OWNERSHIP
(a) Amount Beneficially Owned:
143,000 (as of 12/31/97)
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(b) Percent of Class:
3.31% (as of 12/31/97)
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(c) Number of shares as to which such person has:
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(i) Sole power to vote or to direct the vote
143,000 (as of 12/31/97)
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(ii) Shared power to vote or to direct the vote
-0-
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(iii) Sole power to dispose or to direct the disposition of
143,000 (as of 12/31/97)
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(iv) Shared power to dispose or to direct the disposition of
-0-
-----------------------------------------------------------------
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
If this statement is being filed to report the fact that as of the date hereof
the reporting person has ceased to be the beneficial owner of more than five
percent of the class of securities, check the following. /x/
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
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Not applicable
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ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY
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Not applicable
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<PAGE>
Page 6 of 8
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ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
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Not applicable
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ITEM 9. NOTICE OF DISSOLUTION OF GROUP
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Not applicable
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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.
1/30/98
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(Date)
/s/ Dana Schmidt
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(Signature)
DANA SCHMIDT, CORP. VP & PRINCIPAL
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(Name/Title)
<PAGE>
Page 7 of 8
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ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
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Not applicable
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ITEM 9. NOTICE OF DISSOLUTION OF GROUP
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Not applicable
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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.
1/30/98
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(Date)
Gregory Siemons
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(Signature)
Gregory Siemons, Asst. Secretary
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(Name/Title)
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Page 8 of 8 Pages
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JOINT FILING AGREEMENT PURSUANT TO RULE 13D-1(F)(1)
This agreement is made pursuant to Rule 13d-1(f)(1) under the Securities
Exchange Act of 1934 (the "Act") by and among the parties listed below, each
referred to herein as a "Joint Filer." The Joint Filers agree that a
statement of beneficial ownership as required by Section 13(d) of the Act and
the Rules thereunder may be filed on each of their behalf on Schedule 13D or
Schedule 13G, as appropriate, and that said joint filing may thereafter be
amended by further joint filings. The Joint Filers state that they each
satisfy the requirements for making a joint filing under Rule 13d-1.
Dated: 1/30/98
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MONTGOMERY MICRO CAP FUND MONTGOMERY ASSET MANAGEMENT, LLC
a series of The Montgomery Funds
By: /s/ Gregory Siemons By: /s/ Dana Schmidt
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Gregory Siemons, Asst. Secretary Dana Schmidt, Corp. VP & Principal
