[TenTec] Help for Century 21 with no sidetone

[John Robertson]

Needing some troubleshooting help for Century 21 Analog.

I recently received a Century 21 but the sidetone is not working.

The rig sends a carrier just fine, but I can’t hear the sidetone at all.  I’ve turned the volume pot at the bottom of the board from turn to turn and it has no effect.

The schematic shows some possibilities; the LM3900, the LM380 or perhaps the C2 cap.

Anyone have any suggestions on where to start or you may know of something I’ve overlooked.

As you know, the parts are inexpensive, but the shipping from Mouser will be the same if I need to consider something else so I want to make sure to cover other possibilities.

Any suggestions and help will be much appreciated.

Thanks

John/W5CYF