Board porn

Inside of a old Yamaha Pf10.

Its got an annoying problem: certain notes won't play, or intermittently play.

 Tearing down the key switches.

The keyboard switch assembly. The problem does not seem to be with the switches, but with the wiring harness from the matrix decoder.

In particular, that set of solder points are the bases for the output header. I thought it was the pins, and reflowed the solder, and it all seemed to work.

Sad to say, about a week later, my brother reported the problem had restarted...and he thinks its the ribbon cable that accepts the matrix output.  Maybe so.