Date: Wednesday, 5 June 1985
From:  (unknown)
Subject: TM-2530/2550/2570 MARS/CAP

The TM-2500 series radios may be easily modified for use on MARS/CAP
frequencies from 141-150.995mhz.

Locate the control unit (X54-1860-XX) on the bottom of the radio.  This is
the same board that the TU-7, and or MU-1 are mounted on.  Just to the
left of IC3 you will find a row of diodes.  Cut diodes D8, and D11.  After
the diodes have been cut you will have to "reset" the microprocessor.

Microprocessor Reset.

1. Press and hold the [PS] key.
2. Turn ON the power switch.
3. Release the [PS] key.

All of your programmed data such as memory channel data, DCL data, and
Phone number data will be erased and you will have to reprogram them.  If
the radio is not reset, it will not recognize that you have cut the two
diodes.

 
Copied from the QRZ! Windows Ham Radio CDROM