Dot matrix display issue

KingOfTron

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Man, my pins have really been testing me this week. The current issue of the day is the dmd on my Indiana Jones. It started with vertical lines going down the screen like prison bars, every 5 or 6 dots apart. I swapped out the ribbon cable with another machine, but the lines remained. Next I swapped out the display itself with a brand new one, and now nothing at all comes up, just like it looks when it's off. I switched back to the old display screen, and again a total blank screen. No loose wires, nothing. Any idea what the problem could be without resorting to having to purchase a new driver board?
 
Oddly enough, the screen came back. But I'm positive it's just a matter of time before it goes again.
 
Did it happen again?

Thread Hijack:
I had the company I bought my CV from come out today to swap out the working but on it's way out old DMD for a brand new one........the new one didn't work......we plugged in the old one that was working and now it doesn't work! He replaced the fuses and played with the connectors then left confused and said he'd come back with a new boardin a couple days.

After he left I checked the voltages as suggested at pinrepair.
-118.9 @ Pin 1: -125 volts (-110 to -130 volts); Williams lowered this voltage to -115.
-107.1 @ Pin 2: -113 volts (-98 to -118 volts); Williams lowered this voltage to -103.
Pin 3: Key
Pin 4: Ground
Pin 5: Ground
+5.08 @ Pin 6: +5 volts (4.9 to 5.2 volts)
+11.57 @ Pin 7: +12 volts (10 to 14 volts)
jumps from 1.5 to 37 like crazy! Pin 8: +62 volts (58 to 68 volts)

Any idea was this means? I've been reading trying to figure it out..........if I hold the dmm on pin 8 long enough it will jump up to 50-67v for a second or 2.
 
Did it happen again?

Thread Hijack:
I had the company I bought my CV from come out today to swap out the working but on it's way out old DMD for a brand new one........the new one didn't work......we plugged in the old one that was working and now it doesn't work! He replaced the fuses and played with the connectors then left confused and said he'd come back with a new boardin a couple days.

After he left I checked the voltages as suggested at pinrepair.
-118.9 @ Pin 1: -125 volts (-110 to -130 volts); Williams lowered this voltage to -115.
-107.1 @ Pin 2: -113 volts (-98 to -118 volts); Williams lowered this voltage to -103.
Pin 3: Key
Pin 4: Ground
Pin 5: Ground
+5.08 @ Pin 6: +5 volts (4.9 to 5.2 volts)
+11.57 @ Pin 7: +12 volts (10 to 14 volts)
jumps from 1.5 to 37 like crazy! Pin 8: +62 volts (58 to 68 volts)

Any idea was this means? I've been reading trying to figure it out..........if I hold the dmm on pin 8 long enough it will jump up to 50-67v for a second or 2.
When you test pin 8 try applying pressure (to the side or pushing up) on this pin while testing. If that voltage is jumping in and out I'd bet it's a simple cold solder joint at fault.
By applying pressure one way or another to the pin you should see some results.
 
When you test pin 8 try applying pressure (to the side or pushing up) on this pin while testing. If that voltage is jumping in and out I'd bet it's a simple cold solder joint at fault.
By applying pressure one way or another to the pin you should see some results.

Ok, I tried that and it still jumped around, mainly between 5 - 35 volts. Someone suggested the high voltage is shot...... Do you guys agree? Would the high voltage have anything to do with the neon on my CV not working? I ordered a transformer to try to solve it, but I'm still waiting for it to show up.
 
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