Re: Bellco Golden Bell Credits And Plays but wont skill stop
I'm learning something new about this machine every day! Here's what I discovered by tracing the full signal path through my machine.
The output signal from each stop button travels to the main circuit board via the wide ribbon cable. From there, the signal is used to bias the base of a transistor (one for each stop button) which connects that transistor's collector to ground! The collector is connected to the second wide ribbon cable that eventually makes it's way to the stop board (via the stepper motor connector board atop the reels.)
So where does that measured 5v potential I originally talked about come from???? The stop board! After closer inspection, I found that the stop board receives 24v on pin 1 of it's ribbon cable - which then travels through the fuse and a few resistors then makes its way to a 5v regulator (part number TA78L005AP) which supplies the TTL Logic 5v supply to the ICs and associated stop button circuits.
Therefore, I would suggest you verify you have 24v at the fuse (so you know you have incoming power) and then verify that you do (or probably do not) have 5v coming from the regulator. The most convenient spot to test for that seems to be at the top of capacitor C5 (or pin 14 of ic U1, the hex inverter.)
Let me know if you need me to provide/verify any other voltages.
As for my machine, sorry to hear you don't have a second circuit board on the left side of your cabinet. The machine I'm troubleshooting seems to be somewhat of an anomaly. The second board controls sound, lights behind the reels and the digislo bonus display and lighting. I purchased the machine on the cheap as a project to exercise/improve my troubleshooting skills. It has not disappointed in that regard - LOL. On the bright side, my wife let me purchase some new test gear, so I'm a winner any way you look at it
Hope this info helps you and others.
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