Yamaha EQ Fluorescent Display

Capt Odyssea said:

I've got the Yamaha EQ 500u, One green column of segments ceased working years ago, either channel selected (or both)
60hz Column.(30,--,120, 240, 480, 1k, etc)
Recently, I put it back in service, and I realized it was working again!
Worked for a day or two, then died, worked again the following day then died again and has not worked since.

I was poking around ebay the other day, here is one for sale, lo and behold, same segment is out on this unit also. (it was powered up for the pics)

I have not opened it up yet, anyone dealt with this before?
Cold Solder joint? Bad resistor?
EQ bands all work fine, it just irritates!

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Capt Odyssea said:

Hey Avionic,
put the EQ on the Bench, (piano Stool !!)
and investigated the display, seems to me that the display segments are all "charged" together, all legs from the Actual glass display are obviously into the board behind at the top.
they all seem fine, all lower row of solder joints on that board look fine also,
I twisted the metal tabs straight to separate the Glass display from that PCB board, to check components behind it, but do not want to destroy anything.
Any clues?
I also re-seated the opposite end of the 4 ribbon cables, on the board middle of the chassis.
I'm thinking reheat the pin Solder joints anyway?

What components might be behind that board to cause a problem on one segment only? (or to better describe, one column non working, the 60hz column no matter if left right or both Signals selected for display)

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