I have a Bally Embryon and the displays have a ghosting effect where a digit in the display has a ghost one digit to the left of the digit being displayed. The game came with this problem. I narrowed down the problem to one of the display boards which, when disconnected, causes the problem to go away from all of the other displays. (Note, the problem display will ghost one segment to the right.) I've moved that display to different locations and regardless of where it is located, the ghosting returns when it is plugged in. All of the boards have upgraded resistors (done prior to me owning the game.) The only difference I can tell with the problem board is that the display looks to be replaced (it has commas where the other displays do not.) I've reflowed all the solder joints on the board and have replaced the 7-segment latch (CD4543 4543 IC CMOS BCD to 7-Segment Latch), and the problem has not gone away. I really don't know what I should be testing, so any help will be appreciated.
Ghosting effect. The left "0" is ghosting one segment to the left
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Problem display. Shows ghosting problem, except it ghosts one segment to the right. I move the problem display to the credit/ball slot.
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Problem display disconnected, ghosting effect is gone from the remaining displays
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Top of board of good display.
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Top of board of problem display. Note that the header has been replaced.
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Front of problem display. Note that the display has commas.
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Front of a good display. Note that the display does not have commas.
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Good display not showing ghosting when problem display is disconnected
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