Uniden PC-122, ATTN: Handy Andy

[Retro CB Guy]

Hi, I know this is an older thread but I've got a question about a current issue I'm having.

This is a PC-122, NOT the XL version 1st of all.
Radio works fine but one thing, on RX for USB I can NOT get dialed in on the clarifer at all. Works fine on TX and is on frequency for USB.

What is likely the issue?

73's thanks in advance, Retro

 

[Handy Andy]

Just some quick questions...

Clarifier unlocked?

Has it been "recapped" - if it's OEM - the older caps can "drag down" the voltages used to "trim" the Varactor.

The switch itself, can inject it's own ohmic path, the USB/LSB/AM switch is physical electrical connections - if USB has not been used in a while - the contacts can be oxidized.

Try running - re-melting the soldering pads of the MODE switch to see if the heating can help in the recovery.

To verify this, simply run a DVM to measure voltage across the line from the Clarifier to ground - locate D24 and flip the switch between modes - to check the voltages - a deviation of over 1 volt or "dead" usually means you got to look into the switch or the path from it to D24