Your right we have ruled out the roms. There's got to be a short on the playfield. With just power hooked up to the playfield from the transformer every metal switch is reading 7-8 volts a/c. Even when I pull fuses there is a small amount of a/c present. With all the strobe lines removed and just one return at a time hooked up ( all other returns removed) the switch on that return gives multiple switch closures. It's like voltage is getting on the entire playfield. I did note that while doing this test it only registered switches while I had one hand on the ball/switch and the other hand on the side rail. The saga continues!!
Bally Black Jack switch matrix issue
- Thread starter Mxzmark
- Start date
cdnpinballer
Member
- Nov 15, 2012
- 342
- 13
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luch
Super Member
7-8VAC would suggest there is a GI socket touching something under the PF as GI is approximately 6.3VAC. I would look for a GI lamp socket touching a switch blade or something else under the PF.
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luch
Super Member
is that huge isolator still in the game ? see if you can eliminate it and plug the game in without this , maybe there is a difference
Since the metal on the switch is physically touching the return line on the matrix if I touch the ball to it and then the side rail ( ie ground) would this not pull the line low and register as a closure on the entire return line? Does anyone have an early ss Bally game they could try the same thing on and see if they get the same results.
If you are measuring the voltage from the switch arm through the PF and the metal ball guide, your
If the voltage you are getting is being measured from the switch arm and the metal side rail that the ball is touching, you just need to locate whatever GI socket is touching something it shouldn't be. Check the pop bumper lamp socket leads through the pop coil brakets and everything a GI bulb could come into contact with. Even check the GI sockets in the coin door. I'm pretty sure this stray volatage you're seeing is from a GI string. If the GI string was touching the ball guide I would think it would blow the fuse, so it's likely touching a switch or something else under the PF.
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If the voltage you are getting is being measured from the switch arm and the metal side rail that the ball is touching, you just need to locate whatever GI socket is touching something it shouldn't be. Check the pop bumper lamp socket leads through the pop coil brakets and everything a GI bulb could come into contact with. Even check the GI sockets in the coin door. I'm pretty sure this stray volatage you're seeing is from a GI string. If the GI string was touching the ball guide I would think it would blow the fuse, so it's likely touching a switch or something else under the PF.
D
luch
Super Member
luch
Super Member
Ok the 7 volts is gone from the switches, only 1.5 but I think that is the strobing from the mpu. Don't know how I stopped it but there must be something in a harness, I will further take apart and inspect. However the weird switch issue is still there. Luch when you get home try on your Supersonic it should be very similar to my blackjack. Now that I have the game all back together I played a dozen games and it seems to play fine. Starting to think this may be typical behaviour for these Bally games, how often do you really touch the ball to a switch and the side rail at the same Time... Never. Lol