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Pacman power issue
Question from Clint: Hi, after watching your video on classic power supply testing I recently tested my original Pac Man transformer in same manner and voltage test correct. I then updated the fuse blocks as everyone recommended as well as purchased new power cord from Bob Roberts. After my updates my transformer is reading low voltage: 4.0v, 1.8v, 2.0v and 0 volts instead of 12, 12, 7, 7. I’m testing both at the terminal and fuse block like you did in video. I have 120v measured at the in to transformer and 0 volts on the neutral when game is on and 120volts on both neutral and hot into transformer with power switch off. Also noticed the ISO transformer to monitor is reading low. 120 volts into at the bottom and 0 in at bottom with 40 volts and 19 volts coming out the top.
Did I do something wrong? Transformer or AC filter go bad all the sudden?
Other odd things. If I plug in old original power cord all hot voltage is 60 instead of 120. When game is on and I test voltage on any neutral line with red on that and black on ground neutrals read 0 volts. But if turned off they give the 120volts like hot as Pac Man breaks on/off on a neutral I think.
Thanks for any help
Clint
2 answers
Response from Jonathan: Clint,
This is a very strange issue. I wouldn’t think that the transformer and the AC filter would go bad like that but we have seen stranger things happen. Perhaps you wired the green floor ground wire in place of either the AC hot/line or AC neutral accidently. Probably worth going back and making sure everything is wired properly. Other than that, it’s going to be really hard to troubleshoot this one. You might send us some pictures of the inside of your cabinet if you continue to have issues. That might help us better figure out what’s going on.
Hope that helps. Thank you for your question and good luck with your repair.
Response from Clint: Thanks for your response. I figured out issue. When testing voltage off transformer, I was grounding the multimeter to the AC filter ground or transformer post nut. I didn’t know you had to ground at transformer 0 neutral to get proper ac reading. Same for isolation transformer.
Thanks again. I’m thankful you guys help us noobies in this hobby.
Clint
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