CUSIP NO. 006743306 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. 4)* ADDvantage Technologies Group, Inc. ------------------------------------------------------------------------------- (Name of Issuer) Common Stock, $0.01 par value per share ------------------------------------------------------------------------------- (Title of Class of Securities) 006743306 ------------------------------------------------------------------------------- (CUSIP Number) Kenneth A. Chymiak 1605 East Iola, Broken Arrow, Oklahoma 74012 918-251-2887 ------------------------------------------------------------------------------- (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) January 5, 2006 ------------------------------------------------------------------------------- (Dates of Event which Requires Filing of this Statement) If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of Sections 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 Section 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 persons initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page. The information required on 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). ------------------------------------------------------------------------------- 1. Name of Reporting Persons. I.R.S. Identification No. of above persons David E. Chymiak ------------------------------------------------------------------------------- 2. Check the Appropriate Box if a Member of a Group (a) [ ] (b) [ ] ------------------------------------------------------------------------------- 3. SEC Use Only ------------------------------------------------------------------------------- 4. Source of Funds ------------------------------------------------------------------------------- 5. Check if Disclosure of Legal Proceedings Is [ ] Required Pursuant to Items 2(d) or 2(e) ------------------------------------------------------------------------------- 6. Citizenship or Place of Organization United States of America ------------------------------------------------------------------------------- Number of 7. Sole Voting Power Shares Bene- ficially Owned 2,711,038 by Each Reporting Person 8. Shared Voting Power With 0 9. Sole Dispositive Power 2,711,038 10. Shared Dispositive Power 0 ------------------------------------------------------------------------------- 11. Aggregate Amount Beneficially Owned by Each Reporting Person 2,711,038 ------------------------------------------------------------------------------- 12. Check if the Aggregate Amount in Row (11) Excludes [ ] Certain Shares ------------------------------------------------------------------------------- 13. Percent of Class Represented by Amount in Row (11) 26.9% ------------------------------------------------------------------------------- 14. Type of Reporting Person IN ------------------------------------------------------------------------------- Item 1. Security and Issuer This Amendment No. 4 to Schedule 13D ("Amendment No. 3") amends the Schedule 13D filed on October 14, 1999, as amended by Amendment No. 1 to Schedule 13D filed on October 15, 2004, as amended by Amendment No. 2 to Schedule 13D filed on December 23, 2005, as amended by Amendment No. 3 to Schedule 13D filed on December 30, 2005 (as amended, the "Schedule 13D"), by the reporting person and relates to the common stock, par value $.01 per share ("Common Stock"), of ADDvantage Technologies Group, Inc., an Oklahoma corporation ("ATG"). The principal executive offices of ATG are located at 1605 East Iola, Broken Arrow, Oklahoma 74012. Those items of the Schedule 13D for which there has been no change in the information previously reported are omitted from this Amendment No. 3. Item 2. Identity and Background Item 3. Source and Amount of Funds or Other Consideration Item 4. Purpose of Transaction Item 5. Interest in Securities of the Issuer (a) Mr. Chymiak presently beneficially owns 2,711,038 shares of Common Stock of ATG. The aggregate number of shares of the Common Stock reported herein as beneficially owned by Mr. Chymiak includes the right to acquire 10,000 shares (stock options) granted pursuant to ATG's 1998 Incentive Stock Plan. ATGs Quarterly Report on Form 10-K for the quarterly period ended September 30, 2005, reports that there were 10,096,747 shares of Common Stock outstanding as of December 20, 2005. Mr. Chymiak is therefore currently the beneficial owner of 26.9% of the total issued and outstanding shares of Common Stock. (c) Each of the following sale transactions occurred upon the exercise of an option granted on September 24, 2004, to Barron Partners, LP, pursuant to a stock purchase agreement with option to purchase additional shares (the "Agreement"). The Agreement is described in item 6 of Amendment No. 1, which discussion is incorporated into this item by reference. Date of Disposition Shares Price Disposed by per Sale share January 5, 2006 89,567 $5.25 January 11, 2006 185,433 $5.25 January 13, 2006 78,862 $6.25 January 18, 2006 75,000 $6.25 January 20, 2006 75,000 $6.25 Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer Item 7. Material to Be Filed as Exhibits 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. January 24, 2006 ------------------------------------------------------------------------------- Date /s/ David E. Chymiak ------------------------------------------------------------------------------- Signature David E. Chymiak, Chairman of the Board ------------------------------------------------------------------------------- Name/Title