Re: Gottlieb System 3 Switch Problem - HELP!

Wow, thanks for this feedback, Jim.

So I can answer some of this without hitting the board
First of all, it sounds like my MOSFETs are fine for Q33-44, which I
sort of already figured out, but I appreciate the confirmation.

The drop targets do reset during the solenoid test...to be honest, I'm
not sure why I'm being told I have inoperable switches for SW20,SW30
unless they are supposed to also register a point value when they
fall. Because they don't score when they're hit, but the SW31 behind
the bank registers.

As to the switches, I moved the two suspect switches to a comparable
smart switch location that I knew was working and the suspect switches
worked fine. So I think the switches are OK.

So, am thinking that the problem may be the FETs; perhaps I can't find
the bad ones using the digital multimeter on the diode setting? A
while back I used my DMM to identify a FET that didn't seem to be
working (for the electromagnet Q13) with a FED I purchased from GPE
and it worked.
One option would be to replace the suspect FET if I knew which ones
mapped to them for the four switches. Someone else suggested changing
out the LM339 on the control board (thinking U20C and U19B if I've
mapped it right), but not wanting to mess with that if that isn't the
problem.

Thoughts?
.

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