Raleigh, NC
Disregard
(Topic ID: 234458)
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World Cup Soccer
Bally, 1994
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Quoted from PinballManiac40:Pretty positive that it does but I can't get a great picture off the internet of the board to confirm. You can see in his picture that J107 is disconnected and it does go to coil power.
Are you looking at the WPC-95 driver board by chance?
No, I have a full set of WPC-S schematics. And my tired eyes....My apologies, the Fuse I was looking at on the schematics that looked like 104, was 106. Had to get out the magnifying glass...lol.
Quoted from PinballManiac40:Definitely blowing up his picture looks like it matches rhe original board, though it is hard to make out the numbers.
Could you PM the schematic to me? I cannot find it on the website since it has been updated.
I have the OEM paper copy, booklet form for BSD.
If it's indeed an issue with J107, I would first check each pin with connector removed for continuity to ground, just to rule out a direct short. I don't have the WCS94 schematics, but on BSD, F104 feeds a combination of Low voltage coils and flashers. Since only the flashers might operate in attract mode on power up, I would be looking at those, not the coils.
As a test, if you first confirm that no wires on J107 are direct shorted (especially look at the Red/Wht wire), try removing J122 instead of J107. That's the ground signals for the flashers.
Quoted from PinballManiac40:Just run through the solenoid test with the fuse removed and report the ones not working. Any coils not working, you should inspect the paper coil wrapping for brown or darker discoloration.
[quoted image]
Confused? How does the coil work with the fuse removed?
Also, correct me if I'm wrong, but shouldn't the blanking circuit keep any coils from firing on power up? That's why I initially suspected a flasher.
Quoted from PinballManiac40:Just trying to help identify which coils/flashers use power from the F104. Although, the diagrams from Tlamb should show the same results.
If you have no coils/flashers firing during the tests, make sure you close the coin door for these tests.
The blanking circuit on power up will not keep a locked on transistor from frying a coil.
Ah, gotcha on the fuse. I thought we'd established what F104 fed, but maybe not.
True on the blanking, but if it were a locked on transistor, he would hear the coil turn on during power up. He hasn't mentioned this. He said he checked the coils for shorts and there were none, so it doesn't sound like it's a combination of locked up transistor AND shorted coil that wouldn't turn on.
A good test, might be to watch F104 and see if it blows before or after the blanking completes. Because if it immediately blows on power up before the MPU boots, then it's a good bet that it's a shorted transistor. If it blows after the MPU has booted, then it's likely a shorted flasher in attract mode.
I still vote for removing J122, and possibly the other connectors as the previous poster suggested, and then reinstalling one at a time. Would narrow the scope.
Quoted from PinballManiac40:On top of looking at the coil wrappers, I would pull the MPU board out and test out all the coil/flasher transistors for shorts. Should be quick to test them all.
Testing the transistors in all 3 combinations for shorts
outer to outer pins
middle to one outer pin
middle to other outer pin.
Also a good idea.
Quoted from PinballManiac40:Usually if a coil burns, the coil plunger will not move. You'll need to test the transistor for that kickout coil. as it should definitely be shorted. Best to measure with the coil with an ohmmeter too so we know if the resistance is too low on it or not. Is the paper wrapper burnt at all like in my example picture?
Agree, likely blown transistor. But why did it blow? I would test the coil, transistor and diode on the board for that coil.
Quoted from PinballManiac40:Borderline transistors can breakdown, especially after 20 years, and short causing the coil to lock on when power is applied.
Blown suggests that it is blown open, which will no longer fire a coil and no longer would be blowing out a fuse.
Jeebus...Didn't realize we have the semantics police here. Pardon, me....I agree, the transistor is SHORTED. But still need to check the diode and the coil. No sense in replacing a transistor to just have it blow...er, short, again.
Board isn't 20 years old. It's a new Rottendog.
Quoted from cbdarden:There’s no diode on this particular coil. I’ll have to check for a short on the board.
This is a brand new Rottendog board, kind of annoying if something is wrong with the board itself.
Diodes are not on coils on wpc games...they are on the board.
Quoted from PinballManiac40:If the coil has the right amount of resistance and you cannot see an burn on the coil wrapper, there would not be a need to replace it.
Didn't say replace it...said check it.
Quoted from cbdarden:So, I grounded the black lead and touched all of the transistors and they all beeped from that area: Q64, Q66, Q68, Q70, Q76, Q78, Q80, Q82.
None of the rest beeped. When I remove the plug (J130) from that area, only Q82 beeps.
Is Q82 associated with kickback coil? Don't have schematics in front of me.
Quoted from PinballManiac40:That particular statement was toward the OP in response to his question.
Ah, sorry....it followed my post, so I missed that. Carry on 
Then sounds like you found your culprit. There will be a diode on the collector of that transistor (Outside leg)...Should be physically right next to it. With the same connector off the board, check the diode. Should have ~.6V with black lead on banded side, red lead on other side, DVM in diode mode. Should have OL/Open with leads opposite.
Quoted from PinballManiac40:Great. Time also to look at the coil wrapper and measure the resistance of the coil. Set the meter to 20 ohms. The goalie popper coil is AE-23-800, which is the same as the kickback coil. You can compare the resistance of both and if they measure close, then coil should be ok.
Edit: Rottendog may not use the TIP102 as the original driver board for Q82.
Be sure you check the coil with the connector off the board, otherwise you'll read across the diode on board...if that diode is shorted, you'll read no impedence.
Quoted from PinballManiac40:Nay. Don't worry so much. Only time I had ever seen a diode shorted on the driver board for a coil being shorted, the driver board had a hole in it.
For the time it takes to remove the connector, it's silly not to eliminate that possibility. Troubleshooting 101...minimize possibilities of erroneous readings.
Quoted from PinballManiac40:Better to test the diode in the circuit with the coil. You'll end up doing it at the end anyway.
A shorted transistor to ground, still will not affect the coil resistance measurement either. I even jumpered a coil to ground braid last night and the coil resistance measured the same, grounded or not. Worked just as I expected.
Who said anything about a shorted transistor affecting measurement? I said shorted diode. A shorted diode directly shunts across the 50V and ground lugs of a coil and you would read 0 resistance. You need to lift the connector to both check the diode (otherwise, the diode test will fail across the resistance of the coil), and you need to lift the connector to test the coil in case the diode is shorted. Two tests, one connector lift.
Especially not sure what you meant by "Better to test the diode in circuit with the coil". You can't do that. You always have to lift one leg of the diode off the coil to test. Since these diodes are on the board, you do that by removing the connector. The low impedance of the coil in parallel with the diode will fail the diode test everytime. Instead of reading .6V one way, you'll read ~.1V both ways.
Quoted from PinballManiac40:cbdarden, are you going to be able to change Q82 or have a friend do it? Can you snap a picture of the part? We can help to locate a replacement part. I'm pretty sure it is not the common part found on the original driver board.
https://docs.wixstatic.com/ugd/846ba2_6dcb501571a04b578f46eeea2c69d692.pdf
Looks to be a 20N10L
1 week later
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