I have an old Kenwood TS-7850 2 meter base/mobile...vintage mid 80's.
It does not have PL tone module installed and the manual says that
there are terminals inside and a front panel switch so that a third
party PL module can be installed (only three solder joints). Kenwood
says that they do not make one (at least not at the time).

Does anyone know what might be a suitable 3rd party PL module for this
older rig and where it might be obtained. I have heard of a ComSpec
SS-32, but a net search hasn't found how they are obtainable.

For retaining memory, this unit uses 4 AA nicads. They will hold
memory for about 3-4 day according to the manual. If you keep the
power supply on (not desireable) the batteries will remain charged,
but Kenwood also had the provision for a "wall wart" trickle charger
to keep the batteries charged with out using the main 12v power
source. Kenwood made a module called a BC-1 for this function.
I am also trying to source this item.

Jon W3JT