Scared stiff DMD randomly turns off and on...

GameyMcGame

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Cant figure it out..It'll work for a while and then just go blank...Then back on a little bit later...Maybe its haunted?

I've pulled and re-set all the connections and 'wiggling' the wires doesnt do anything...Thoughts?
 
Check your voltages when it is working, are they within specs? Are they all there when it goes off?
 
If the voltages disappear or drop when your display goes blank then your display power supply board needs work.
 
Check your schematics and see if the power is still getting to the high voltage power supply board. This will tell you if the problem is on that board or before it. Sounds like something is heating up.
 
ok, I just checked the voltages. The -113 and -125 are non existant (when its out).

So what am I looking at here?

Go to Ed at Great Plains Electronics and get his high power rebuild kit for your DMD driver board.

LTG :)
 
Ok...so, I had the pin on for about 3 hours today. Played a few games, dmd was great. Turned right on and never died. Then, while it was on, opened up the coin door, to replace the coin return bulbs. In doing that, I hit the slam switch and the game did its slam/tilt thing AND. The dmd turned off. Never to come back on. Wtf?

Also, anyone repair the driver board? I don't think my soldering if up to snuff. Thanks
 
no, i saw it but others asked for me to do the swap, which I did...

I've never had the issue before so I guess my question is, would a bad HV create an intermittent scenario like I have?
 
You'll find the high voltage section has tons of cold solder joints due to the tremendous heat generated in that area of the board. This can cause intermittent problems.

Even those large 5 watt resistors go bad.
 
You'll find the high voltage section has tons of cold solder joints due to the tremendous heat generated in that area of the board. This can cause intermittent problems.

Even those large 5 watt resistors go bad.

So pull and check for cold solder is next I suppose? Thanks ken
 
no, i saw it but others asked for me to do the swap, which I did...

I've never had the issue before so I guess my question is, would a bad HV create an intermittent scenario like I have?

Hmmm, never saw the swap comment.

Swapping the DMD is a great idea but that only tells you if the DMD is working correctly.

Never a bad idea to install the HV components anyways. And in my opinion replace all of the ribbon cables in any WPC/WPC95 pin that you are going to keep long term.
 
Hmmm, never saw the swap comment.

Swapping the DMD is a great idea but that only tells you if the DMD is working correctly.

Never a bad idea to install the HV components anyways. And in my opinion replace all of the ribbon cables in any WPC/WPC95 pin that you are going to keep long term.

Yeah, was actually a pm I got about it...strangely enough, when I push on the pcb I can get a second or two of video on the dmd...strange
 
Ken said it! "Cold solder joints' Pushing on it made something make connection, resolder the board!!
 
great vids, thanks guses.

Ok, so, I hit up the solder and it didnt help.

Just curious, if I wanted to replace the driver board, I assume it would be this one:

http://rottendog.us/WDB095.htm

$250 is crazy particularly when the 89's are only like $100....

Any other options if I just want to put a new board in here and not pay a fortune?

Thanks
 
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