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                                                                   EXHIBIT 31.2


                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER


I, Alan B. Catherall, certify that:

1.       I have reviewed this annual report on Form 10-K of Numerex Corp.;

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 periods 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)       [omitted pursuant to the guidance of Release No. 33-8283
                  (June 5, 2003)]

         c)       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

         d)       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 (the
                  registrant's fourth fiscal quarter in the case of an annual
                  report) 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 the registrant's board of
directors (or persons performing the equivalent functions):

         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, 2005

                                     /s/  Alan B. Catherall
                                     ------------------------------------------
                                     Alan B. Catherall
                                     Chief Financial Officer
                                     Executive Vice President, and
                                     Principal Financial and Accounting Officer


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