WG monitor issues / want to redo power in cab

Hey guys,

***Here's my new question, since grounding the bejesus out of everything doesn't affect my problem. I want to redo power in this cab. Right now it appears to have like 3 different boxes that the line goes through, and I'm sure it's not very good, and probably what's causing the interference. Question is: What do I need? An arcade switching power supply I know... what specs on the isolation transformer? what's an AC line filter? do I need anything besides these three items? where do I fuse? **




Ok so I finally got a nice working double dragon board, fired it up and its all working great. The monitor (Wells-Gardner, don't see any model #s though) was way out of whack so I did some adjustments and now its great all except for two things. One is that the horizontal width needs to be increased, and secondly I see diagonal wavy lines.

Now since there are no other problems, I dont' think a cap kit is necessary. I read on some arcade archive that adding a ground wire from the monitor chassis to the regular board ground would probably solve the interference issue, so I'll try that when I get home.

About the horizontal width, I've figured out that I have to adjust that coil, but I've also heard that it falls apart often. So should I only adjust (with a plastic tool) when it's turned off, in case it disintegrates? Or is that a less common issue than people make it seem.

Any other ideas on the wavy lines might be nice too.

Adding the ground worked great. I found a spade that obviously used to have a ground on it, so I added it back on, wavy lines are goneskis.

What about the width issue, did you tweak the coil ?

not yet, gotta hit Canadian Tire or Home Depot and find a plastic hex.

Hmm actually, it turns out adding the extra ground wire didn't work. Nor did connecting field ground on the power supply to ground.

Now the power supply seems to be ok for the most part, but the screws are all rusted. The 5V showed 5.4, i moved it down to 5.05 with no change in operation or the interference. Do you guys think maybe I need a new switching power supply to deal with the rusting? Is it an indication of problems on the inside? Or just get some new screws?

Post pics please.

http://callan.batcave.net/error.htm

Above has two pictures worth noting. One is the PS, other is the monitor chassis board. The sync part has no ground on the ground pin, could that be the source? I couldn't grab a picture of the interference because it is quite faint. But its just like other interference, diagonal ghost lines that move in one direction, slow down, and reverse direction over and over.

oh, and the extra red wires were added by me, as i said above from the chassis to the rest of the grounds. No change. I originally thought it fixed the problem, but it takes about 10 seconds for the problem to become really apparent.

updated the first post.

Well adding a new power supply never hurts, especially when the current one in there may be the original.
Check out Bob Roberts' site on AC wiring arcade cabs.
http://therealbobroberts.net/acwiring.html
His website is a little tricky to navigate but there is tons of great info about everything arcade.
Also another thing that never hurts to do is a cap kit on your monitor. Wells Gardner monitors are known for their quality but caps get old and need to be replaced eventually.
Another thing to note is that the monitor doesn't get power from the power supply (you may already know that). It get's power from the 120v line from the wall.

Thanks gunbu,

but the monitor should get it's power from the secondary side of the isolation transformer, no?

currently in my cab, the power goes through a unit that makes use of the switches around the cab to turn on the power (ie back door must be closed, coin door must be closed), then it goes through a big transformer that has 2 120vac outputs and a 6.3v (i think) for the lighting. Right now only one of the 120vac lines is used, and it goes from the iso trans to the switching power supply, and keeps going to the monitor. should these be separated? could this be the cause of the interference?

ok, this will probably be my last post in this thread. I moved my arkanoid power supply to the double dragon and no interference was present. I think a new PS is all I need. thanks to everyone who helped out!