One final problem I've been having with this synthesizer restoration
project for a friend.

I've reassembled the synthesizer and noticed that the membrane switches
on the front panel weren't functioning properly. I traced it back to a
certain connector on the board - when I tug upwards on the wires leading
to the header the buttons function normally, but when I relax them slack
and let everything rest normally the buttons stop functioning again.

I've lifted up the board and tested continuity between the soldered PCB
pins and the points where the wires from the membrane button board enter
the detachable header while connected and everything tests fine, so I'm
not exactly sure what the problem is...

On 11/04/2016 05:05, bitrex wrote:
One final problem I've been having with this synthesizer restoration
project for a friend.

I've reassembled the synthesizer and noticed that the membrane switches
on the front panel weren't functioning properly. I traced it back to a
certain connector on the board - when I tug upwards on the wires leading
to the header the buttons function normally, but when I relax them slack
and let everything rest normally the buttons stop functioning again.

I've lifted up the board and tested continuity between the soldered PCB
pins and the points where the wires from the membrane button board enter
the detachable header while connected and everything tests fine, so I'm
not exactly sure what the problem is...

Assuming an indirect connector, try cleaning contact surfaces and then
pack out the reverse side with some mica sheet