Bullwinkle
Member
Williams Flash Pinball, I think I'm in Audit mode...
Well, I finally have my first pinball purchase, a Williams Flash. I'm quite excited about it as the playfield is in great shape. So here's where I am. There was a bad -100vdc transistor in the high voltage area of the power supply board, so I replaced that with a new equivalent as they no longer make the SDS-202 transistor (I've been following the repair guide on pinrepair.com...so yes, i crossed the legs). As a precaution, I also did many of the upgrades suggested on pinrepair (replaced the +5/+12 filter capacitor, the smaller diodes in the high voltage area, pin connector at J6). Once completed, I tested the output voltages and got the following:
connector,pin = reading (acceptable range)
J6, pin6 = 12.85vdc (10 to 14vdc)
J6, pins 7 thru 10 = 5.09vdc (4.9 to 5.2vdc)
J5, pin4= 97.62vdc (90 to 105vdc)
J5, pin3= -97.43vdc (-90 to -105vdc)
J4, pins 5 thru 8= 20.23vdc (16 to 20vdc) "a little high"
J3, pins 6 thru 8= 37.65vdc (28 to 38vdc)
The only thing out of line was the J4 connector being a bit high. will that be an issue? What I get is the control display showing 04 00 (and the 4 flickers to an 8) ...I can hit the test switch on the door and the 00 will advance and display 1 will show some random numbers occasionally as the value increases. I flip the toggle switch on the door and the numbers decrease as I hit the test switch.
With the values from the PSB looking ok, i did test points on the CPU board and got the following voltages (didn't have alligator clips, so I couldn't get some of the values when switches are depressed or during that 1 second during bootup)
test point, reading, (expected value)
TP1, 11.04vdc (12v)
TP2, 4.5vdc (5v normal operation, 0v when diagnostic switch depressed(untested))
TP3, .05vdc (should be +5 when interlock closed, 0vdc when interlock open, can I assume interlock was open as I have no idea what that means?)
TP4, 4.97vdc (5vdc normal operation, 0vdc for 1 sec after boot)
TP7, 4.7vdc (4.3vdc when powered, 3.9vdc when off - I have no batteries in(untested))
TP8, 4.93vdc (5vdc normal operation, 0vdc for 1 sec after boot(untested))
TP9, 5.02vdc (5vdc)
The battery area looks very clean, but I intend to remove the housing and verify no corrosion has occured.
TP1 is unregulated so I'm not sure what that value should be or if it's in the proper range. TP2 was low and TP4 was high. Should I check the power coming into the CPU board at the connector to verify the power is making it through the cabling correctly? or does it seem like the CPU is in need of some chips/repair that is beyond what I should attempt (being my first pin and all). I have no problems soldering pcbs so this may be a repair I can handle. (I work on arcade pcbs and monitors as well as computer based time and access control devices, so I'm good with a soldering station)
In everyone's experience, is this something I should be able to correct eventually or should I send them out? If I send them out, is there someone in here that works on these? I'm confident my power supply board is fine based on my readings, so it would be my CPU, interconnect and possibly control display.
Thanks
Tom
Well, I finally have my first pinball purchase, a Williams Flash. I'm quite excited about it as the playfield is in great shape. So here's where I am. There was a bad -100vdc transistor in the high voltage area of the power supply board, so I replaced that with a new equivalent as they no longer make the SDS-202 transistor (I've been following the repair guide on pinrepair.com...so yes, i crossed the legs). As a precaution, I also did many of the upgrades suggested on pinrepair (replaced the +5/+12 filter capacitor, the smaller diodes in the high voltage area, pin connector at J6). Once completed, I tested the output voltages and got the following:
connector,pin = reading (acceptable range)
J6, pin6 = 12.85vdc (10 to 14vdc)
J6, pins 7 thru 10 = 5.09vdc (4.9 to 5.2vdc)
J5, pin4= 97.62vdc (90 to 105vdc)
J5, pin3= -97.43vdc (-90 to -105vdc)
J4, pins 5 thru 8= 20.23vdc (16 to 20vdc) "a little high"
J3, pins 6 thru 8= 37.65vdc (28 to 38vdc)
The only thing out of line was the J4 connector being a bit high. will that be an issue? What I get is the control display showing 04 00 (and the 4 flickers to an 8) ...I can hit the test switch on the door and the 00 will advance and display 1 will show some random numbers occasionally as the value increases. I flip the toggle switch on the door and the numbers decrease as I hit the test switch.
With the values from the PSB looking ok, i did test points on the CPU board and got the following voltages (didn't have alligator clips, so I couldn't get some of the values when switches are depressed or during that 1 second during bootup)
test point, reading, (expected value)
TP1, 11.04vdc (12v)
TP2, 4.5vdc (5v normal operation, 0v when diagnostic switch depressed(untested))
TP3, .05vdc (should be +5 when interlock closed, 0vdc when interlock open, can I assume interlock was open as I have no idea what that means?)
TP4, 4.97vdc (5vdc normal operation, 0vdc for 1 sec after boot)
TP7, 4.7vdc (4.3vdc when powered, 3.9vdc when off - I have no batteries in(untested))
TP8, 4.93vdc (5vdc normal operation, 0vdc for 1 sec after boot(untested))
TP9, 5.02vdc (5vdc)
The battery area looks very clean, but I intend to remove the housing and verify no corrosion has occured.
TP1 is unregulated so I'm not sure what that value should be or if it's in the proper range. TP2 was low and TP4 was high. Should I check the power coming into the CPU board at the connector to verify the power is making it through the cabling correctly? or does it seem like the CPU is in need of some chips/repair that is beyond what I should attempt (being my first pin and all). I have no problems soldering pcbs so this may be a repair I can handle. (I work on arcade pcbs and monitors as well as computer based time and access control devices, so I'm good with a soldering station)
In everyone's experience, is this something I should be able to correct eventually or should I send them out? If I send them out, is there someone in here that works on these? I'm confident my power supply board is fine based on my readings, so it would be my CPU, interconnect and possibly control display.
Thanks
Tom
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