Skateball
Bally, 1980This one is puzzling me. I’ve got 43V DC at all the coils, and I can activate each coil by grounding its transistor tab on the solenoid board. I know the game isn’t tilted, because scores go up when I hit drops and switches, etc. The coils don’t activate in test mode either.
My best guess right now is that U2 is bad on the solenoid driver board. Anything else I should check? Everything was working fine yesterday.
Verify you didn't lose your ground to the SDB. I guess you could have lost U2, or possibly the 5 volts to U2. (Open run on the SDB)
Can you go to test and scope the inputs and outputs of U2 to see what's happening? You might be able to use an analog voltmeter - just look for the needle jumping back and forth.
Quoted from Billc479:I guess you could have lost .... possibly the 5 volts to U2.
Check this ^^^ first. Measure the voltage at test point TP3 on the solenoid driver board. Very common problem with an issue on that brown-green loop back wire connection at J3.
Ya’ll nailed it! TP3 was 0V, so I jumpered J3 pins 13 and 25 with a test lead. All good now! I think I’ll rebuild that whole connector. For now though, I’ll just jumper pins 13 and 25 on the back of the board. Thank you so much! I just finished a playfield swap and I was worried it was something I’d done.
Crazy design…
I believe it was done that way to get a safety certification even though it does zero to make the game safer.
Quoted from Billc479:You may want to read up on it on pinwiki, including the ground mods. Some disapprove, but I do the mods on any of the SDB’s I rebuild.
Some food for thought:
https://pinside.com/pinball/forum/topic/stern-flight-2000-power-on-hum-resolved
Quench - interesting. It seems like a speech board issue? Regardless, part of the issue may be my partial deafness - I never noticed any issue. If you can't hear it, it doesn't matter.
Like you, I've always done the mods, even though Big Al disapproves. I will have to think about this.
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Pleasant Plains, IL