Dr who lightning strikes twice !

[carl lawrence]

Was giving my dr who a bit of a shake down after I repair the expander board and notice every time the ball goes around the right ramp the up kicker would work . I go into switch edge test and any switches that’s in that column would trigger off the 3 optos . Lucky I was able to take a board from revenge from mars ,which uses the same board to see if it was a board fault . Hurray no double or triple activations ,just good old single switch activation . Let’s have a closer look at the opto board as I see a cap on it
I just don’t believe it !!

 

[Pick Holder]

Yeah - I change a lot of capacitors these days in 90s games as they are all drying out - or worse still - LEAKING.

 

[carl lawrence]

When i spotted what looks like a water bubble I just couldn’t believe it .
I have ordered a new one but want to repair this one .
Just looking at pinwick now it looks like i need to replace the lm 339s

 

[carl lawrence]

Just a little update on this I fitted the new opto board and the ground fault was still there which completely confused me as I was 100% sure it was that .so I ran with the conclusion to replaced J206 connector completely which is the column connector . and Bingo that was the answer a bad connection all this time !