monitor board smoking

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Quite the pin head here with the first Jamma vid and a problem. I got this 48-1 clone in a nice cab and a great monitor. My problems were with the wiring in the cab being all taped up. So I fixed that and the joystick tape also removed. Then came the cord. Sure a new one of those would be great. What a 2 prong... Joke so I put a 3 prong on it and grounded it to the power supply tower. Turn the machine on and smoked the big board on the side of the monitor. Now I took my time and did all the soldering correctly. One at a time. The only change was the ground cord to the case of the power supply. I took off the board from the monitor and the ground traces are gone. Smoked them right off the board. Well 2 of them anyway. Fuse blown and it was the correct one. Now I put new traces on the board and removed the ground from the power supply. Now the thing just blows the fuse. Please advise me as to what needs to be replaces / max probibilities. Thanks.
 
Sounds like you pumped some major voltage through the ground trace on the monitor. Your monitor may be one that requires and isolation transformer, and the way you wired it up may not have had an isolation transformer in the circuit.

If your fuse is blowing continuously, you should check that your rectifying diodes/rectifier on the chassis aren't shorted, your voltage regulator on the chassis isn't shorted, or that your Horizontal Output Transistor (HOT) isn't shorted. If those all check out, then you could suspect the flyback, or any other little part on the chassis. Look around for blown caps, too...
 
It did have a tag on it that stated it needed an isolation transformer on it. So I am a bit screwed on this one just because I hooked up the ground to the circut. I will go a head and print out your check list and do that tomorrow. Thanks.
 
Well, the isolation transformer supplies your 120vac to your chassis power input. Hooking up a free ground to a power supply casing shouldn't cause a problem, unless it wasn't a free ground wire at all....
 
There is no isolation transformer in the cab, just a power supply tower. The monitor is run right off of the ac line input on the power supply. Is the fly back the small board on the back of the monitor. It states "High Voltage"? Also is the big board to the right of the monitor a Chassis? If so then How do I get that board out of the machine. Last night I ran traces with it just hanging off of the monitor. There is a round rubber plug that goes to the monitor that I was not touching. I do not know how to get zapped OR avoid getting zapped when dealing with a vid.
 
Well, running the monitor without an isolation transformer when you need one means your rectifier section and voltage regulator are probably toast now. That power supply you have just passes AC through to the monitor. You need a transformer so that there is no direct connection between the wall AC and the monitor, otherwise you get feedback that smokes the monitor.

If you post a picture of the back of your monitor, I can identify the model, and tell you the best way to get it out to work on it...
 
Super. Now all I have to do is figure out how to post a picture. Tomorrow I have a Super Auction in LA to go to.. should I look for a cabinet with an isolation tranformer in it? Would it be better for me to get a cab that has a monitor / iso transformer / and just swap out parts? or is the fix fairly easy. I am a parts buying crazy man and can install better than the factory(or so I think). However this is my first vid fix and my meter is being a pain right now. I need a new meter. Seems that a power reg and diodes would be a snap. However the wiring and figureing out what / how / correct / Iso transformer is / looks like / needs to be is the question. I assume that a Iso transformer is just a transformer of some sort that is seperate from the power supply and running to the monitor ac only. It would have 110 in and 110 out but this is only guessing. I did not make it to my shop today so I did not get a chance to check your list of possables. Might get a good picture or two tomorrow night after the auction.; Sunday is the Delmar races so that looks to be out also. About 6 years ago I bought 50 arcade manuals. I kept the vids seperate and still have them. I have 6 or so manuals about the monitors. I will try to match them up to the cab monitor I have the next time I am at the shop. I will check for replys in the morning before I leave. Around 8 am. Thanks.
 
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