My Pinball machine was acting strange. Sometimes the wrong sound would play, and intermitant 7 segment displays not displaying properly.
I did a check on the test points of my AS 2518-54.
TP1: 3.7 DC volts <-- This should be closer to 5 - 5.8
TP2: 230 DC volts
TP3: 15 DC volts
TP5: 45 DC volts
TP4: 6.4 AC volts
I'm at a loss why my display issue is occuring because the display voltage looks good.
Its this a bridge rectifier issue or a transformer issue ?
Quoted from legtod2:TP1: 3.7 DC volts <-- This should be closer to 5 - 5.8
Half voltage on TP1 usually indicates a diode internal to bridge rectifier BR1 on the rectifier board has an open circuit fault. This usually means the feature lamps only get half voltage so appear dimmer than they should. It will not cause any other game issues.
Quoted from legtod2:Its this a bridge rectifier issue or a transformer issue ?
Your fault descriptions are vague (when does it play the wrong sound, displays not displaying properly in what way?) but chances of them being bridge rectifiers or transformer considering your other voltages are good is extremely unlikely.
Quench
Sound issue. Playing the wrong sound references like "Welcome to Xenon" when a target is hit.
Doesn't TP1 lead supply MPU 5DC Volts or it there some other power supply for the MPU ?
Display Issue. The 7 segment display segments will flicker with one segment brighter than another.
Quoted from legtod2:Sound issue. Playing the wrong sound references like "Welcome to Xenon" when a target is hit.
Are you using a factory MPU board or repro?
There's 4 signals from the MPU board (J4 pins 1 through 4) that go to both the solenoid driver board and the sound board (J1 pins 1 through 4) used to select solenoids and sounds. Check both connectors for good connectivity.
Quoted from legtod2:Doesn't TP1 lead supply MPU 5DC Volts or it there some other power supply for the MPU ?
Nah, MPU 5VDC is generated by a 5 volt regulator on the solenoid driver board that's powered from the 12V rail coming from the rectifier board - this is your TP3 reading of 15V which is in spec.
Quoted from legtod2:The 7 segment display segments will flicker with on segment brighter than another.
Presume this is only one display? which segment is it?
Quoted from legtod2:Here is a youtube to demonstrate the behavior I was talking about on the 7 segment display
Ok, I've always known that as wavy digits and I can't remember specifically which pin but it's always been cracked solder joints on the display board pin header and/or pins to the plasma itself. Pull that display out and look at the soldering. Should be obvious but if not use a magnifying glass.
Quoted from legtod2:It has a new Alteksystems.com mpu board in it
Can you confirm 100% if the Alltek "CLK speed" jumpers (top left of the board) are both set to Bally which is the right side positions? Having them set on Stern MPU-200 has been known to cause wrong sounds with some Bally sound boards.
After I reseated score display number one (removed the cable on player score 1 and re-connected), the wavy display issue moved to score display number three. At the moment player score one is perfect.
Quoted from legtod2:After I reseated score display number one (removed the cable on player score 1 and re-connected), the wavy display issue moved to score display number three. At the moment player score one is perfect.
Reflow all the header pins on the displays, almost mandatory in my experience.
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