Wells Gardner D9200 - Horizontal Collapse?

[Rocketeer2001]

Hey Shawn, thanks for the detailed explanation. I was so caught up just trying to get the EGA signal into a CGA signal that I totally neglected how this would affect the light gun.

Guess I'm back to trying to fix the D9200. I'll start by removing the power supply caps and testing them. Maybe one of them has gone bad despite being replaced already.

[lilshawn]

if you are going to gung ho it, disconnect the 190v rail from the SMPS power supply and load it with a bulb, (remove inductors or diodes on the output side of the main 190v and then connect a 60 watt INCANDECANT lightbulb between there and ground) if it doesn't light up, issue with SMPS or other low voltage SMPS circuits... if it does glow, move up the line... "cut" out the horizontal deflection (which also runs on 190v) and see if it powers on. if it does, issue is in deflection. if it does not power on now, issue is in HV/flyback.

remember we only want to run it for a few seconds at a time just to see if the power supply kicks on.

basically all we are doing is trying to isolate where the short is originating from.

alternatively, if you have a bench power supply capable of supplying a good few amps, you could just slam some power into the 190v into the circuit till whatever is shorted heats up (and you can ID it with a temp gun thermometer or IR camera) or blows up in a puff of smoke. not ideal and possibly kill something else at the same time, but it will reveal the culprit.

[Rocketeer2001]

Shawn, as discussed through PM's, I was ready to go gung-ho but then I came across another Big Buck Hunter 2 for sale. It was missing some parts, but what it did have is a different 27" trisync monitor; a Neotec NT-500DX. Per our discussion, it sounded like a more solidly engineered piece of tech and would be easier to fix. Yes, even this monitor was broken...

However, the cost for the whole cabinet (with basically spare parts for my arcade) was low, so I bought it! I've already begun dismantling it to fix the monitor, so the D9200 will be on hold for now. Just looking at the chassis board for the NT-500 is like a breath of fresh air. It's just so well organized and spaced out in comparison.

Anyone following this thread, I might be back to fix the D9200 if the Neotec fails me, but I don't see that happening. I'll report back in either case.

[Rocketeer2001]

One last thing I did before giving up on this monitor was adding a power LED.

I recall reading somewhere in a post that if you had a D9200 with a power indicator LED on it, if it lit up it meant your power section was up and running. I think...I can't find that post again, so someone else will have to confirm. I found on the schematics where the LED would have been, so I wired one in.

I drilled a 5mm hole in the large heat sink at the back of the board to mount a 5mm LED. That way you could see it easily when the board was in the arcade machine.
I ran a positive red wire to J029 and a negative black wire to J030.
I added a resistor to the LED to step down the voltage to 2.1v.

Tossed the board back in the machine and tested it out. It works! Not sure if this officially means my power section is good or at the very least that the 5v rail works. Anyways, maybe this is helpful for someone else with a D9200.