SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 AMENDMENT NO. 4 Alpha Industries, Inc. - -------------------------------------------------------------------------------- (Name of Issuer) Common Stock - -------------------------------------------------------------------------------- (Title of Class of Securities) 020753109 - -------------------------------------------------------------------------------- (CUSIP Number) Check the appropriate box to designate the rule pursuant to which this Schedule is filed: [x] Rule 13d-1 ( b) [ ] Rule 13d-1 ( c) [ ] Rule 13d-1 ( d) 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 in the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities and 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).13G Cusip No. 020753109 - -------------------------------------------------------------------------------- 1. Name of Reporting Person S.S. or I.R.S. Identification No. of Above Person Westport Asset Management, Inc. - 06-1087640 Westport Advisers LLC - 06-1497709 --------------------------------------------------------------------------- 2. Check the appropriate box if a member of a group* (a) [ ] (b) [X] --------------------------------------------------------------------------- 3. SEC Use Only --------------------------------------------------------------------------- 4. Citizenship or Place or Organization Connecticut - -------------------------------------------------------------------------------- 5. Sole Voting Power 167,550 Number of ------------------------------------------------------------ Shares 6. Shared Voting Power Beneficially 1,369,600 Owned By ------------------------------------------------------------ Each 7. Sole Dispositive Power Reporting 167,550 Person ------------------------------------------------------------ With 8. Shared Dispositive Power 1,640,400 - -------------------------------------------------------------------------------- 9. Aggregate Amount Beneficially Owned by each Reporting Person 1,807,950 --------------------------------------------------------------------------- 10. Check Box if the aggregate amount in row (9) excludes certain shares [x] 5,300 --------------------------------------------------------------------------- 11. Percent of Class Represented by Amount in Row 9 4.2% --------------------------------------------------------------------------- 12. Type of Reporting Person* IA - -------------------------------------------------------------------------------- Item 1(a): Name of Issuer: - ---------- --------------- Alpha Industries, Inc. Item 1(b): Address of Issuer's Principal Executive Offices: - ---------- ------------------------------------------------ 20 Sylvan Road Woburn, WA 01801 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: - ---------- ------------ Connecticut Item 2(d): Title of Class of Securities: - ---------- ----------------------------- Common Stock Item 2(e): CUSIP Number: - ---------- ------------- 020753109 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 (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) (X) Parent Holding Company, in accordance 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. - ------- ---------- (a) Amount Beneficially owned: 1,807,950 shares (b) Percent of Class: 4.2% (c) Number of shares as to which such person has: (i) sole power to vote or to direct the vote: 167,550 (ii) shared power to vote or to direct the vote: 1,369,600 (iii)sole power to dispose or to direct the disposition of: 167,550 (iv) shared power to dispose or to direct the disposition of: 1,640,400 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: - ------- ---------------------------------------------------------------- Item 7. Identification and Classification of the Subsidiary Which - ------- acquired the Security Being Reported on By the Parent Holding Company. ----------------------------------------------------------------- Item 8. Identification and Classification of Members of the Group. - ------- ---------------------------------------------------------- N/A Item 9. Notice of Dissolution of Group. - ------- ------------------------------- N/A 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 - ---------- 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 12, 2001 Westport Asset Management, Inc. By /s/ Andrew J. Knuth ---------------------------- Andrew J. Knuth, Chairman