V5000 Video Plus not functioning correctly

[DougB]

I just received a slot machine from a friend, a Bally V5000 Video Plus.  He bought it new in 89 and mid way through had to replace the main PCB.  He said that now it's doing the same thing that it was (the screen is garbled).  Every time I turn it on the screen is garbled but when I press some of the user buttons on the front I can get it to show the main screen but it's not functioning per say.  At the bottom of the main screen there is garbled data that is always the same so perhaps it's giving useful info?  I suspect I may need to replace the main PCB but I am hoping someone might be able to give some advice or point me in the right direction. 


Thanks in advance for any advice you might be able to offer. 


-Doug

[Neonkiss]

Bottom two pictures don't look that bad, so I would re-seat the graphics chips on the board.
The 5000's were notorious for bad power supplies, so check voltages.
If at start up you get the top screens and then after warm up you get the two bottom pictures, I would check the capacitors on the monitor.

[DougB]

Thank you very much for your comments Neonkiss.  I reseat all of the chips on the main PCB as well as all of the power connections and wore a static strap just to be better safe than sorry.  Two things happened:


1. I can no longer get the two bottom screens. 
2. Despite not getting the bottom screens, prior to that the compare hardware for the coin did not appear to be working.  The quarter would always dump in to the main change area outside the door.  Now, when it boots up the screen is all garbled.  At this time the change thing doesn't work but if I press the reset button just once you will see some sort of pulsing static on the screen even though the garbled text is still there but now the coin comparitor works perfectly.  So I take it that the coin comparitor receives some instruction from the main board and now it appears to be getting that even though nothing else appears to do anything.  Although the coins go in to the correct hopper, there is no sound of any sort and no light change nor does the monitor.  Perhaps I have only put it in a diagnostics mode by pressing the reset button. 


If the problem were caps in the monitor then I would expect it to take coins and for something to happen.  Perhaps your right about the power supply.  I have a schematic so I will go through that in the next several days to see what I can find. 


Thanks,
[size=78%]Doug [/size]