Wells 25k7193 keeps blowing fuses - Page 1
Forum section: electronics / beginners

author: scooter350z
author_rank: Newbie
timestamp: February 10, 2020, 12:51:27 am
content: Hello all.First post on the site, and hoping someone might be able to give me some help. I have a Golden Tee 2005 arcade that I did a good self-inflicted wound to.I was adjusting the screen on it, and fixing the marque light, and the game was looking better than it has in years after the adjustments. Right before I was ready to call it a day, I moved the power supply abit, and it ended up arcing on an exposed connection. The wire that the power supply case hit was going to the coin slot terminal on the jamma board. Immediately the everything shut off. I inspected the jamma connector and pcb and the traces, and found that the monitor ground trace had vaporized right at the jamma wire connection. I did not notice any other visible damage to the board.I was able to solder in a bypass wire on the board and confirm it had contact back to its original path. Plugged jamma back in with high hopes, and got nothing. Hard drive spins, pcb seems to boot up with green leds everywhere, but no sound, and nothing from the monitor, not a single sound over the hard drive.I start to investigate on the monitor chassis, and notice the fuse is popped. Again with high hopes, I swapped the fuse and it instantly blew again taking the wind right out of my sails again. I have pulled the chassis, and there is no sign of burns, loose connections, or damage of any kind. All of the caps look good visually. I then unplugged the power from the chassis (line/neutral), and powered up the machine with a new fuse again with only the rgb, ground, sync wires connected, since that was the ground that melted the trace on the pcb. The fuse did not blow. But, I then connected power to chassis again, and it blew instantly. So, that is where I am at. A pcb that may or may not be working, and a screen that instantly blows fuses when supplied power. The supply power is 120v when checked to the monitor.I am energetic to fix myself, but it is not in my wheelhouse. There unfortuneatly is nobody in my area that knows how to repair these things, or nobody returns my calls that advertises that they do. So it kind of puts it back into my lap.Here is the chassis model, and tube model. Wells Gardner 25k7193 manu date Sept 1993. Tube- Phillips mva63aam08xAfter research, this seems to be a pretty common chassis and tube for arcades of the era, and looks like parts are very available. In other words, fixable I assume. I have downloaded diagrams of the chassis, and parts list, but, I am still pretty new to reading and fully understanding everything. But I should have enough to atleast understand some replies that I hopefully get. HahaSo that is the back story. My main question is, has similar symptoms happened to anyone else and they found the fix, or does something pop out as apparent from my description that I can test next to narrow things down? I currently only have a multimeter for testing. I can supply any pics needed for clarification, but again, there is no visible damage anywhere.One thing I did find strange, is the lack of a ground wire coming anywhere off of the chassis, or monitor frame. Only the monitor ground through the rgb ground sync connection. Which is the connection at the jamma connector which got fried on the pcb. Is this correct with no other ground wire?Thank you for any replies and help with this. Sorry so long winded, but wanted to get all the details in.