The racal Cougar PRM4515H can operate in a 20Mhz band across 132-174Mhz  UK police forces used these and they are now appearing on the surplus market. However there are two variants one that was used by Police force surviellance units H3TKU and one H3TCU that was used by Regional crime squads. The H3TCU can be used as is for the 2m amateur band. However the H3TKU must be reconfigured to operate in the 2m amateur band.

The bands are configured by changing the position of 4 SMD 1M ohm resitors on the RF board.

The band the set is configured for is indicated according to the details below.

H3TAU  132-151.9875Mhz H3TBU  134-153.9875Mhz
H3TCU  136-155.9875Mhz H3TDU  138-157.9875Mhz
H3TEU  140-159.9875Mhz H3TFU  142-161.9875Mhz
H3TGU  144-163.9875Mhz H3THU  146-165.9875Mh
H3TIU  148-167.9875Mhz H3TJU  150-169.9875Mhz
H3TKU  152-171.9875Mhz H3TLU  154-173.9875Mhz






7 of the 12 configurations allow operation in the 2m amateur band without any modifications to the band selection resistors.

To convert the others:-        

First remove the battery, antenna and handset then open up the set by removing 9 screws from the case on the serial number side.

The screws are captive in the back casing and don't need to come all the way out of the back casing.

Then remove 4 screws from the RF board

You should be able to see the location of the resistors in the next picture Note the small screwed coax plug top left this can be unscrewed and the board removed completely or left on and the board worked on in situ.

Here is a close up with the resistors configured for 150-169.975Mhz

By moving the resitors different bands can be selected


I've programmed 145Mhz channels into it and after doing the carrier squelch modification below have been listening to my local VHF repeater. The signal is a bit down compared to my normal handheld so I will have to retune C13 and L4 on the front end at some point.

Link to conversion of PRM4515H and PRM4515L to carrier squelch.   PRM4515 CARRIER SQUELCH

Here is a link to the Cougar operators cards         Racal PRM4515 operators cards


R36 and R37 control the time out timer and can be set for 30, 60, 90. 120 seconds the radio above is set for 120 seconds


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D. J. MCKAY G1JWG 2017