X's & O's
Bally, 1983I've swapped out the acid damaged MPU and replaced it with an Alltek board and the game works perfectly. My one big issue is the ball/credit display doesn't work at all, it doesn't even glow slightly like the others do when no digits are displayed. I recently bought a replacement 6 digit display and it's having the same issue. All other displays work perfectly fine.
Any ideas as I'm totally stumped?
You mentioned no glow - did you verify voltages on the display board? Since you had acid damage, I would look closely at the plugs that feed the displays from the MPU-its possible you have corroded pins.
Did you check your settings - on free play the credit unit does not show, may not be related, but...
Quoted from Billc479:You mentioned no glow - did you verify voltages on the display board? Since you had acid damage, I would look closely at the plugs that feed the displays from the MPU-its possible you have corroded pins.
Did you check your settings - on free play the credit unit does not show, may not be related, but...
I've just tested Voltages, the non working display is recovering just over 3Volts while the others are getting about 175Volts. This is my first SS game so any suggestions on what's causing the low voltage at that display only?
Thanks,
James
James -
Test the high voltage at the connector pin on both ends. It should read about 175VDC. If you're missing the high voltage at the display only, but have it at the MPU end, then you have a bad wire/pin. If you don't have the high voltage at each pin (At the MPU and at the display) then you have an issue at the MPU board. You should be able to access the side of the pin with the connectors on.
Its possible that you have a corrosion damaged pin at the MPU connector that feeds the voltage to the display. Repinning that entire connector is likely the best thing to do.
As an aside, to verify a corroded pin, insert a paper clip into the pin a few times, then connect the connector and see if the display comes back. If it does, then you have a corroded pin and should replace all the pins on that connector. This may not always work, but its worth a try.
It should go without saying, but do this with power off. Also, do not connect and disconnect the connectors with power on. You can really mess something up.
Quoted from Billc479:James -
Test the high voltage at the connector pin on both ends. It should read about 175VDC. If you're missing the high voltage at the display only, but have it at the MPU end, then you have a bad wire/pin. If you don't have the high voltage at each pin (At the MPU and at the display) then you have an issue at the MPU board. You should be able to access the side of the pin with the connectors on.
Its possible that you have a corrosion damaged pin at the MPU connector that feeds the voltage to the display. Repinning that entire connector is likely the best thing to do.
As an aside, to verify a corroded pin, insert a paper clip into the pin a few times, then connect the connector and see if the display comes back. If it does, then you have a corroded pin and should replace all the pins on that connector. This may not always work, but its worth a try.
It should go without saying, but do this with power off. Also, do not connect and disconnect the connectors with power on. You can really mess something up.
Please excuse me for sounding stupid here. (I've always been an EM guy) which wire is it on the connector that's actually carrying the voltage? The MPU is a brand new Alltek board so is it reasonable to presume the issue is not at that end? I also don't quite understand how to test the voltage of each pin while it's connected.
Again, sorry if my questions sound dumb haha
James -
If you look at the connector, you will see that on one side, you can see the sides of the pins. Clip your ground to the ground braid in the bottom of the head, or to a ground test point on the display board. (TP3 on the display board) Touch the side of the pin with your other meter lead. (You will have to look at the schematic for the pin number.) You should read the 175 volts. If not, verify you are reading the 175 volts at the other end of the wire. Again, see the schematic for the pin number. I don't have a schematic in front of me to give you the pin number.
The following link will give you more information about troubleshooting Bally, just look at the sections for the displays and troubleshooting displays. I think you have a voltage problem, which is why the display is not working. Look at the pictures of the various connectors, you will see what I mean about one side of the connector pins being visible. Your meter tip will need to be small enough to touch the pin between the plastic housing.
http://pinwiki.com/wiki/index.php?title=Bally/Stern#Displays
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Chelmsford
Pleasant Plains, IL