Exhibit 31.2

                                 CERTIFICATION

I, Geoffrey F. Feidelberg, certify that:

1.          I have reviewed this amendment No. 1 to the annual report on Form
            10-K/A of CompuDyne Corporation;

2.          Based on my knowledge, this report does not contain any untrue
            statement of a material fact or omit to state a material fact
            necessary to make the statements made, in light of the circumstances
            under which such statements were made, not misleading with respect
            to the period covered by this report;

3.          Based on my knowledge, the financial statements, and other financial
            information included in this report, fairly present in all material
            respects the financial condition, results of operations and cash
            flows of the registrant as of, and for, the period presented in this
            report;

4.          The registrant's other certifying officer and I, are responsible for
            establishing and maintaining disclosure controls and procedures (as
            defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
            registrant and have:

                        (a) Designed such disclosure controls and procedures, or
            caused such disclosure controls and procedures to be designed under
            our supervision, to ensure that material information relating to the
            registrant, including its consolidated subsidiaries, is made known
            to us by others within those entities, particularly during the
            period in which this report is being prepared;

                        (b) Evaluated the effectiveness of the registrant's
            disclosure controls and procedures and presented in this report our
            conclusions about the effectiveness of the disclosure controls and
            procedures, as of the end of the period covered by this report based
            on such evaluation; and

                        (c) Disclosed in this report any change in the
            registrant's internal control over financial reporting that occurred
            during the registrant's most recent fiscal quarter that has
            materially affected, or is reasonably likely to materially affect,
            the registrant's internal control over financial reporting; and

5.          The registrant's other certifying officer and I have disclosed,
            based on our most recent evaluation of internal control over
            financial reporting, to the registrant's auditors and the audit
            committee of registrant's board of directors:

                        (a) All significant deficiencies and material weaknesses
            in the design or operation of internal control over financial
            reporting which are reasonably likely to adversely affect the
            registrant's ability to record, process, summarize and report
            financial information; and

                        (b) Any fraud, whether or not material, that involves
            management or other employees who have a significant role in the
            registrant's internal control over financial reporting.

         Date:  May 11, 2007
                                             /s/ Geoffrey F. Feidelberg
                                            ----------------------------
                                            Geoffrey F. Feidelberg
                                            Chief Financial Officer