DMD out on Data East Tommy

Grantman

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I think this happened before and it was a fuse but I checked all the fuses this time and they are fine. The cables seem fine. The 5V connection appeared to be 4.75V. Any other common reasons that the display would be totally out?
 
have you checked any other voltages for this? im not 100% but im pretty sure you should also have some higher voltages aswell a +5 volt source

i may be wrong, but from what i understand from the schematic is as follows
on the dot matrix board at P1
you should have
pins 1-8
1 yellow/black -110 vdc
2 grey/yellow -98 vdc
3 key
4 yellow ground
5 black ground
6 red +5 vdc
7 blue +12 vdc
8 violet/yellow +68 vdc


correct me if im wrong so i can make sure im right next time
 
Last edited:
i may be wrong, but from what i understand from the schematic is as follows
on the dot matrix board at P1
you should have
pins 1-8
1 yellow/black -110 vdc
2 grey/yellow -98 vdc
3 key
4 yellow ground
5 black ground
6 red +5 vdc
7 blue +12 vdc
8 violet/yellow +68 vdc

This is what I'm getting:

pin 1: -4V
pin 2: -4V

pin 6: 5V
pin 7: 12V
pin 8: 23V

So something is clearly wrong. Can this be fixed or does this mean I need a new power supply board?
 
You can buy a new PS, but PSes are very simple to fix if you can do board work. Do you know anyone that can work on it?
 
You can buy a new PS, but PSes are very simple to fix if you can do board work. Do you know anyone that can work on it?

Not really. I'd like to get this working by this weekend because I'm having people over. I'm going to try to swap it out.
 
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