Stromberg-Carlson 1212 Fatboy xmit trouble

[bnaOldPhones]

Having a strange problem with my S-C fatboy.  The receive audio path works great, but the audio on the transmit path is weak and fades in and out (like listening to a shortwave radio!).  This is not a problem with my phone system; other phones work fine.

What's the most likely culprit?  The transmitter module itself?   Any ideas for a fix would be appreciated ...

[LarryInMichigan]

The transmitter capsules are often weak or bad.  The first things to try would be to remove the capsule, tap it on a hard surface to loosen the carbon granules and shake it a bit, and clean the contacts in the handset and on the transmitter.

Larry

[bnaOldPhones]

Thanks!  I tapped the capsule a little when I rebuilt the phone, but I'll give it another good once-over and clean up the contacts.