Yaesu YC-7B repair

My trusty YC-7B counter, part of my FT-7B setup, decided it was time to play tricks on me. The counter started to trip wildly, displaying frequencies between zero and 100 MHz, and all within one second. After checking for all the obvious defects (cables, connectors etc), I disconnected the counter to look at it later.

Squeeze it a bit
I mentioned the problem on a local repeater, and another FT-7B owner replied “Squeeze it a little bit.” Huh? Oh well, April 1 was still far away, so I connected the counter again and squeezed it a bit in the middle. The counter stopped tripping. Ah! The problem didn’t really go away though, but it gave a good idea where to look: a connector, connecting the top board to the bottom one.

Repair is a big word
Separate the upper and lower circuit board, spray a little contact cleaner into the connector, manually clean the contacts of the upper circuit board, reassemble the counter and you’re done.

The problem area, marked in red

Spray some contact cleaner into the connector

The contacts, after some cleaning