Eight Ball Deluxe
Bally, 1981I just acquired an Eight Ball Deluxe. Early on in games, the knocker coil seems to be firing and adding a credit totally at random. I’m nowhere near any bonus scores. Happens maybe once or twice each game. I’ve gone through the door settings. I’m not seeing anything obvious. The first credit threshold is set for 600,000. I’m getting credits added at less than 100,000 or 200,000. Any ideas? Am I missing something. Thanks.
Quoted from YeOldPinPlayer:Awarding a special maybe? Any playfield inserts marked special?
I don't think so but I will double check.
Quoted from phillyfan64:I just acquired an Eight Ball Deluxe. Early on in games, the knocker coil seems to be firing and adding a credit totally at random. I’m nowhere near any bonus scores. Happens maybe once or twice each game. I’ve gone through the door settings. I’m not seeing anything obvious. The first credit threshold is set for 600,000. I’m getting credits added at less than 100,000 or 200,000. Any ideas? Am I missing something. Thanks.
What are the other two thresholds set at? Order is not important, score is.
Quoted from dothedoo:What are the other two thresholds set at? Order is not important, score is.
600,000 and 1,100,000. Also I checked and there are no specials lit so it's not that. It just seems to be random. Maybe a flakey transistor? It's an original driver board.
Quoted from phillyfan64:600,000 and 1,100,000. Also I checked and there are no specials lit so it's not that. It just seems to be random. Maybe a flakey transistor? It's an original driver board.
If it's just knocking at random then it could be driver board related, but if it's also adding credits then it's definitely software controlled. You may have to zero out every setting and re-enter score thresholds or possibly the CMOS RAM is flaky and needs to be replaced.
Quoted from dothedoo:If it's just knocking at random then it could be driver board related, but if it's also adding credits then it's definitely software controlled. You may have to zero out every setting and re-enter score thresholds or possibly the CMOS RAM is flaky and needs to be replaced.
Thanks. I'll try zeroing everything out. I'm new to the settings of this game so I'm still learning the ins and outs. Would it help to unplug it and take the battery out?
I reset the 600,000 and 1,100,000 scoring thresholds to zero and then back to normal. I also cleared the high score to date. No change. It seems like it may be tied to the rollovers. It seems like if I hit A,B,C,D and then maybe B,D a 2nd time the knocker fires and adds a credit.
Also if A or B at the top is hit while the yellow arrow is lit, the left sling shot fires. Issues related or 2 separate issues?
Quoted from DNO:FYI, there is a third scoring threshold
Yes, it’s set to zero.
The driver board had some issues with bad tracings and a couple bad transistors. I replaced it with an Alltek driver board and the issue appears to be resolved. I haven’t done anything with the MPU board. I don’t understand it, but it’s working.
It would be funny if a switch was out of whack, with a "hair trigger", and the knocker vibrations would rack up credits. That would fit the circumstances, new driver board stops the random knocker, and the random credits.
I will run through the switch test tonight but since switching boards I have not been able to get it to act up. Played at least 10 games and also took the glass off and ran over all the rollovers manually several times. Nothing unusual.
Something that has not been mentioned for future reference is the the playfield switch capacitors (related to the speed of signal processing to the MPU), which is not related to the solenoid driver board in any manner.
Bally was cheap, similar to their "fast acting" diodes.
Failing (shorting) capacitors CAN cause this effect on the knocker (through other switch activations) and other solenoids via causing confusion into the switch matrix of the MPU-35.
MISSING capacitors in critical locations can do this as well.
Check, and test them across the game.
They were designed to "charge" a switch in order to allow the game to more quickly register the switch hits.
Alsos test the diode on the knocker assembly.
I have seen this firsthand.
In fact, I recently fixed a Paragon (MPU-17 versus 35, but essentially the same circuit theory) that was doing exactly the same thing.
I had a similar intermittent problem when I built my EBD Classic.
All this is AFTER eliminating MPU settings (in the case of the knocker scoring setting with credit adds which if set TOO LOW, will knock and add credits, check it in the diagnostics menu), connectors, wiring issues, and switch sensitivities in this exact order.
Afterwards keep going "up the chain" further all the way to the MPU into the PIAs.
It seems unnecessary for anyone to recommend spending $200 on standard diagnostic fix that is correctable, as long as the MPU is in good working order and not corroded. I never saw the board, so I don't know its actual condition, and it may have been required to be replaced anyway.
New boards do not always fix problems, if the problem was never determined in the first place.
It called "swaptronics" (ie guessing) and is a bad practice because a person does not learn repair skills, and the new board can be damaged immediately and permanently meaning the person has to repair or replace a new board again after finding the real problem.
Thanks for the info and advice. I actually didn’t order the board for this issue. I ordered it because a couple drop targets were failing the solenoid test. I did try fixing the board but somebody really butchered it. It worked for a few games and then failed again due to the bad tracing. This game doesn’t always register in the C,D and two special outlane rollovers when the ball goes over them really fast. I did adjust those switches but maybe it needs more tweaking or caps there. Anyway I will definitely do some more testing. Thanks.
Quoted from xTheBlackKnightx:In fact, I recently fixed a Paragon (MPU-17 versus 35, but essentially the same circuit theory) that was doing exactly the same thing.
Paragon has a sound board. It is a -35 just like Eight Ball Deluxe.
I stand corrected, both games do use a Bally MPU AS-2518-35. Not a -17 from games like SS Mata Hari. Principle of diagnotic troubleshooting for MPU switch processing is identical.
I mistyped thinking about other common problem areas such as the AS-2518-50 versus the AS-2518-61A used in EBD, which is not relevant to this direct issue.
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