PROSPECTUS SUPPLEMENT                     Filed Pursuant to Rule 424(b)(3)
(To Prospectus dated March 11, 2004)           Registration No. 333-112851

                               CalAmp Corp.

     This Prospectus Supplement supplements and amends the joint proxy 
statement/prospectus on Form S-4 filed February 13, 2004, as supplemented 
on March 11, 2004 (the "Prospectus") relating to the shares of the common 
stock, par value, $0.01 per share (the "Common Stock"), of CalAmp Corp., 
formerly known as California Amplifier, Inc., a Delaware corporation 
("CalAmp"), issued to the selling stockholders in connection with the 
merger between Vytek Corporation, a Delaware corporation ("Vytek"), CalAmp 
and Mobile Acquisition Sub, Inc., a Delaware corporation and wholly owned 
subsidiary of CalAmp ("Merger Sub"), whereby, among other things, Merger 
Sub was merged with and into Vytek and Vytek became the surviving 
corporation and a wholly owned subsidiary of CalAmp. 
     The disclosure in the Prospectus set forth under the heading "Where 
You Can Find More California Amplifier Information" is supplemented by 
adding the following sentence before the fourth paragraph in that section:
     This joint proxy statement/prospectus also incorporates by reference 
     any documents that we file with the SEC under Section 13(1), 13(c), 
     14 or 15(d) of the Exchange Act after the date of this prospectus 
     until the offering is completed (other than Current Reports furnished 
     under items 9 and 12 of Form 8-K).

     Any statement contained in the Prospectus shall be deemed to be 
modified or superseded to the extent that information in this Prospectus 
Supplement modifies or supersedes such statement.  Any statement that is 
modified or superseded shall not be deemed to constitute a part of the 
Prospectus except as modified or superseded by this Prospectus Supplement.
     This Prospectus Supplement should be read in conjunction with, and 
may not be delivered or utilized without, the Prospectus.  This Prospectus 
Supplement is qualified by reference to the Prospectus, except to the 
extent that information contained in this Prospectus Supplement supersedes 
the information contained therein.

     This investment involves risks.  See the section entitled "Risk 
Factors" beginning on page 18 of the attached Prospectus for a discussion 
of the risks that you should consider before purchasing our Common Stock.
     Neither the Securities and Exchange Commission nor any state 
securities and exchange commission has approved or disapproved these 
securities or passed upon the adequacy or the accuracy of this prospectus, 
as supplemented.  Any representation to the contrary is a criminal 

              Prospectus Supplement dated October 8, 2004.