[Test-Equipment] Motorola service monitor

[KD5SFA]

I have a friend with a older Motorola service monitor that is having a problem.
Tracking down documentation is hard as the model number varies with the various plug in module options.

It is the type with a frequency synthesizer on the bottom and 4 - 6 bays for plugin modules.
The problem is that the pll on the frequency synthesizer does not lock so the unit is pretty much useless.
We are trying to locate schematics and hopefully some documentation on it.

I can hopefully post a part number tomorrow for the frequency synthesizer as I don't have it with me.

We have seen variations of it sold but no manuals.  Google searches have turned up very little useful info.
Any suggestions on sources for manuals or other information ?

73,
Jon
KD5SFA