Check power cable connections, fuses, and ignition sense wire.
: Specification sheets and brief user guides are frequently found on Key Considerations motorola gm series vhf - service manual - Elektrotanya
: Comprehensive lists of internal components for replacement. Signaling Information motorola gm3688 service manual upd
Checking voltage regulators, internal fuses, and ignition sense lines.
The rear of the GM3688 includes an expanded 16-pin accessory interface utilized for data telemetry, GPS tracking modules, public address setups, or external ignition switching. Motorola Long Range 25W Mobile Radio GM3688 Check power cable connections, fuses, and ignition sense
Visual aids for locating parts on circuit boards.
: Motorola no longer manufactures new GM3688 units, but you can find information on upgrades, replacements, or repairs on their discontinued products page. The rear of the GM3688 includes an expanded
: Details for the 16-pin external port used for integrated solutions like GPS/AVL systems.
Due to copyright, the best places to find these manuals are technical repositories.
The mainboard can be accessed by unscrewing the back heatsink assembly.
Connect the radio to a service monitor, transmit a carrier wave, and adjust the electronic potentiometer via the Motorola Customer Programming Software (CPS) Tuner until the frequency error is minimized (typically within +/- 1.5 ppm). 2. Transmitter Power Tuning