OK, so I'm playing a game and going really well - next thing the left flipper starts acting up - WTF!
Lift the playfield, snoop around looking for the obvious, broken wires, diodes across the coil - the usual suspects. Nothing. Look in the backbox at the fliptronics board, connectors all seem OK, nothing is obviously frizzled????
Go back to basics and start at the actual switch. I remember that these optos do cause problems on the actual flipper button board so I rip it out and lo and behold - the board is covered in corrosion! I cleaned it up as best I could and resoldered a few suspect joints. Bridged one track that was very suspicious. Put it all back together and BINGO! All spot on. So in this case the optos are fine but the PC board has corroded.
I trawled the usual suppliers and the best price I could find was $34 each - ridiculous for such a small board with 2 resistors, 2 optos and a connector on it!
So this became the next Homepin project - jumping the cue of other boards we are making. Artwork is complete and already submitted to the PCB fabrication factory. Finished boards should be about 2 weeks and I estimate a pair should cost about $39, maybe a few dollars more depending on the final costs.
We added some test points for checking 12V right at the board and also have made up a laser cut insulator to install between the board and the metal flipper actuator to help prevent a repeat of the corrosion.