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_____________________________
| OMB APPROVAL |
| OMB No. 3235-0145 |
| Expires September 30, 1988 |
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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 1)*
Protocol Systems, Inc.
- --------------------------------------------------------------------------------
(Name of Issuer)
Common Stock
- --------------------------------------------------------------------------------
(Title of Class of Securities)
74371R10
- --------------------------------------------------------------------------------
(CUSIP Number)
Check the following box if a fee is being paid with this statement [XX]. (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 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).
(Continued on following page(s))
Page 1 of 6 Pages
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CUSIP NO. 74371R10 13G PAGE 2 OF 6 PAGES
------------------ -- --
- ----------------------------- -----------------------
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
WESTPORT ASSET MANAGEMENT INC.
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [ ]
(b) [X]
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3 SEC USE ONLY
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4 CITIZENSHIP OR PLACE OF ORGANIZATION
CONNECTICUT
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5 SOLE VOTING POWER
NUMBER OF 84,600
SHARES -----------------------------------------------------
BENEFICIALLY 6 SHARED VOTING POWER
OWNED BY
EACH 610,500
REPORTING -----------------------------------------------------
PERSON 7 SOLE DISPOSITIVE POWER
WITH
84,600
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8 SHARED DISPOSITIVE POWER
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9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
695,100
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10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
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11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
7.8%
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12 TYPE OF REPORTING PERSON*
IA
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*SEE INSTRUCTION BEFORE FILLING OUT!
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Page 3 of 6 pages
Item 1 (a) Name of Issuer:
- ---------- ---------------
Protocol Systems, Inc.
Item 1 (b): Address of Issuer's Principal Executive Offices:
- ----------- ------------------------------------------------
8500 S.W. Creekside Place
Beaverton, Oregon 97008-7107
Item 2 (a): Name of Person Filing:
- ----------- ----------------------
WESTPORT ASSET MANAGEMENT, INC.
Item 2 (b): Address of Principal Business Office:
- ----------- -------------------------------------
253 RIVERSIDE AVENUE
WESTPORT, CT 06880
Item 2(c): Citizenship:
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CONNECTICUT
Item 2(d): Title of Class of Securities:
- --------- -----------------------------
COMMON STOCK
Item 2 (e): CUSIP Number:
- ---------- -------------
74371R10
Item 3. If this stated 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(b)(6)
of the Act
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Page 4 of 6 pages
(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
Advisors Act of 1940
(f) ( ) Employee Benefit Plan, Pension
Fund which is subject to the
Provisions of the Employee Retire-
ment Income Security Act of 1974
or Endowment Fund; see 'SS'240.13d-1
(b)(1)(ii)(F)
(g) ( ) Parent Holding Company, in accor-
dance with 'SS'240.13d-1(b)(ii)(G)
(Note: See Item 7)
(h) ( ) Group in accordance with
'SS'240.13d-1 (b)(1)(ii)(H)
Item 4. Ownership.
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(a) Amount Beneficially owned: 695,100 shares
(b) Percent of Class: 7.8%
(c) Number of shares as to which such person
has:
(i) sole power to vote or to direct the
vote: 84,600
(ii) shared power to vote or to direct the
vote: 610,500
(iii) sole power to dispose or to direct the
disposition of: 84,600
(iv) shared power to dispose or to direct
the disposition of: 610,500
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Page 5 of 6 pages
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 ( )
Item 6. Ownership of More than Five Percent on Behalf of Another
- ------ --------------------------------------------------------
Person:
-------
A PORTION OF THE SHARES OF COMMON STOCK OF THE ISSUER
REPORTED HEREBY, AMOUNTING IN THE AGGREGATE TO 6.8% OF
SUCH SHARES OUTSTANDING, ARE HELD IN CERTAIN DISCRETIONARY
MANAGED ACCOUNTS OF WESTPORT ASSET MANAGEMENT, INC. (THE
"REPORTING PERSON"). THE REMAINING SHARES OF COMMON STOCK
OF THE ISSUER REPORTED HEREBY, AMOUNTING TO 0.9% OF SUCH
SHARES OUTSTANDING ARE BENEFICIALLY OWNED BY OFFICERS AND
STOCKHOLDERS OF THE REPORTING PERSON. THE REPORTING PERSON
DISCLAIMS BENEFICIAL OWNERSHIP OF SUCH SHARES BENEFICIALLY
OWNED BY SUCH PERSONS AND DISCLAIMS THE EXISTENCE OF A
GROUP.
Item 7. Identification and Classification of the Subsidiary
- ------- Which acquired the Security Being Reported on By
the Parent Holding Company.
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N/A
Item 8. Identification and Classification of Members of
- ------- the Group.
------------------------------------------------
N/A
Item 9. Notice of Dissolution of Group.
- ------- -------------------------------
N/A
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Page 6 of 6 pages
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 purpose
or effect.
Disclaimer
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The undersigned expressly declares that the filing
of this Schedule 13G shall not be construed as an
admission that such person is, for the purpose of Section
13(d) or 13(g) of the Securities Act of 1934, the
beneficial owner of any securities covered by this
statement.
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.
Date February 19, 1998
WESTPORT ASSET MANAGEMENT, INC.
BY /s/ ANDREW J. KNUTH
ANDREW J. KNUTH, CHAIRMAN
STATEMENT OF DIFFERENCES
The section symbol shall be expressed as...................................'SS'
