The PCGM (Programmable Clock Generator Module) is a device used for some configurations
of simulcast with the RTCM. For transmitters that can "swallow" a 10 MHz external reference clock source
(such as the Motorola Quantar, etc), all you need is the output of the RTCM driving the direct
modulation of the transmitter. For radios that do not have an external reference clock source
(or have one, but not at 10MHz), the PCGM will take the 10Mhz reference from the GPSDO (generally
a Trimble Thunderbolt) and "make" whatever frequency your transmitter needs for a reference
(at least one of 17988 frequencies possible). Transmitters that do not have an external reference
clock input at all generally need to be modified to disconnect the normal internal reference oscillator
and make provisions to allow injection of the reference clock frequency from the PCGM.

In addition the PCGM also generates the voltages (3 of them, I believe) to run the Trimble
Thunderbolt, with a single (generally 12 volt) input to the PCGM.

These devices are available for sale from the Micro-Node.Com site.

There was also a question on the list about the ClockSynth project. This was merely an initial prototype
to prove the base design of the PCGM. There were only 2 boards of this type built. They worked and
demonstrated the validity of the general concept from which the PCGM was then based.

Jim WB6NIL