UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D (Amendment No. 16)* Under the Securities Exchange Act of 1934 CSP Inc. (Name of Issuer) Common Stock (par value $0.01 per share) (Title of Class of Securities) 126389105 (CUSIP Number) Melissa Dehn 2219 Buchanan Road, Suite 9 Antioch, CA 94509 (925) 778-2390 (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) September 16, 2005 (Date of Event which Requires Filing of this Statement) If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this schedule because of 240.13d- 1(e), 240.13d-1(f) or 240.13d-1(g), check the following box [ ]. Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See 240.13d-7 for other parties to whom copies are to be sent. *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). CUSIP No. 126389105 SCHEDULE 13D Page 2 of 6 1 Names of Reporting Persons Eliot Rose Asset Management, LLC IRS Identification No. of Above Persons (entities only) 04-3649045 2 Check the Appropriate Box if a Member of a Group* (a) [ ] (b) [ ] 3 SEC USE ONLY 4 Source of Funds OO 5 Check Box if Disclosure of Legal Proceedings is Required Pursuant to Items 2(d) or 2(e) [ ] 6 Citizenship or Place of Organization Rhode Island NUMBER OF 7 Sole Voting Power -0- SHARES BENEFICIALLY 8 Shared Voting Power -0- OWNED BY EACH REPORTING 9 Sole Dispositive Power 836,199 PERSON WITH 10 Shared Dispositive Power -0- 11 Aggregate Amount Beneficially Owned by Each Reporting Person 836,199 12 Check Box if the Aggregate Amount in Row 11 Excludes Certain Shares [ ] 13 Percent of Class Represented by Amount in Row 11 23.30% 14 Type of Reporting Person OO, IA CUSIP No. 126389105 SCHEDULE 13D Page 3 of 6 1 Name of Reporting Person Gary S. Siperstein IRS Identification No. of Above Person 2 Check the Appropriate Box if a Member of a Group* (a) [ ] (b) [ ] 3 SEC USE ONLY 4 Source of Funds OO 5 Check Box if Disclosure of Legal Proceedings is Required Pursuant to Items 2(d) or 2(e) [ ] 6 Citizenship or Place of Organization California NUMBER OF 7 Sole Voting Power -0- SHARES BENEFICIALLY 8 Shared Voting Power -0- OWNED BY EACH REPORTING 9 Sole Dispositive Power 836,199 PERSON WITH 10 Shared Dispositive Power -0- 11 Aggregate Amount Beneficially Owned by Each Reporting Person 836,199 12 Check Box if the Aggregate Amount in Row 11 Excludes Certain Shares [ ] 13 Percent of Class Represented by Amount in Row 11 23.30 14 Type of Reporting Person IN CUSIP No. 126389105 SCHEDULE 13D Page 4 of 6 Item 1. Security and Issuer This Schedule 13D ("Schedule") relates to shares of Common Stock, par value $0.01 per share (the "Common Stock"), of CSP Inc. (the "Issuer"). The principal executive office of the Issuer is 43 Manning Road, Billerica, Massachusetts 01821-3901. Item 2. Identity and Background This Schedule is filed on behalf of Eliot Rose Asset Management, LLC and Gary S. Siperstein. Eliot Rose Asset Management, LLC is an investment advisor registered as such with the SEC and in various states. Eliot Rose Asset Management, LLC's managing member and majority owner is Gary S. Siperstein. The business address of Eliot Rose Asset Management, LLC and Gary S. Siperstein is 10 Weybosset Street, Suite 401, Providence, RI 02903. Neither Eliot Rose Asset Management, LLC, or Gary S. Siperstein have, during the past five years, been convicted of any criminal proceeding (excluding traffic violations or similar misdemeanors). Neither Eliot Rose Asset Management, LLC or Gary S. Siperstein, have been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws. Eliot Rose Asset Management, LLC is a Rhode Island limited liability company, and Gary S. Siperstein is a United States citizen. Item 3. Source and Amount of Funds or Other Consideration Funds for the purchases of Common Stock were obtained from the working capital of various accounts managed by Eliot Rose. Item 4. Purpose of Transaction. The acquisition of Common Stock was made solely for investment purposes. Depending upon market conditions and other factors, Eliot Rose Asset Management, LLC may acquire additional securities of the Issuer, or alternatively, may dispose of some or all of the securities of the Issuer that it beneficially owns. CUSIP No. 126389105 SCHEDULE 13D Page 5 of 6 Item 5. Interest in Securities of the Issuer (a),(b) Reference is made hereby to Items 7-11 and 13 of pages two (2) and three (3) of this Schedule, which Items are incorporated by reference herein. (c) Eliot Rose Asset Management, LLC effected the following transactions through a registered broker dealer in the last sixty days, or since the last filing: Transaction Date Amount of Securities Price sell 8/30/2005 27 $6.86 sell 8/30/2005 100 $6.97 sell 8/30/2005 100 $7.03 sell 8/30/2005 320 $7.08 sell 8/30/2005 200 $7.11 sell 8/30/2005 253 $7.22 sell 9/2/2005 1,500 $7.11 sell 9/6/2005 100 $7.01 sell 9/6/2005 100 $7.03 buy 9/7/2005 6,500 $7.05 buy 9/9/2005 3,500 $7.67 buy 9/12/2005 5,000 $7.65 sell 9/12/2005 1,000 $7.33 buy 9/13/2005 25,000 $7.61 Deliver Out 9/14/2005 2,500 N/A buy 9/16/2005 5,000 $7.51 (d),(e) Not applicable. Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer None. Item 7. Material to be Filed as Exhibits None. CUSIP No. 126389105 SCHEDULE 13D Page 6 of 6 Signatures After reasonable inquiry and to the best of their knowledge and belief, the undersigned certify that the information set forth in this statement is true, complete and correct. DATED: September 27, 2005 Eliot Rose Asset Management, LLC /s/ Gary S. Siperstein ______________________________ Gary S. Siperstein Managing Member Gary S. Siperstein /s/ Gary S. Siperstein ______________________________ Gary S. Siperstein