Dead Pacman? Help!

Jeff M

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I've been trying to get rid of the annoying hum bar problem. I replaced both fuse blocks, new fuses, reflowed solder, new connector, and capped the k4600 monitor. Plugged the pacman in and everything worked great except the hum bar was still there. So I pulled out the pacman board and replaced only three caps from bob roberts pacman cap kit and decided to turn it on to just see. After I flipped the switch now I get this faint red screen and nothing else. Did I kill the pacman board somehow?

I replaced both the 10000uf 10v caps and the one 2200uf 25v cap. If I remember correctly.
 

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I've been trying to get rid of the annoying hum bar problem. I replaced both fuse blocks, new fuses, reflowed solder, new connector, and capped the k4600 monitor. Plugged the pacman in and everything worked great except the hum bar was still there. So I pulled out the pacman board and replaced only three caps from bob roberts pacman cap kit and decided to turn it on to just see. After I flipped the switch now I get this faint red screen and nothing else. Did I kill the pacman board somehow?

I replaced both the 10000uf 10v caps and the one 2200uf 25v cap. If I remember correctly.

I can help you better if you provide a pic of the caps that you replaced, I want to see if you put them in right.
 
Did you make sure the edge connector went back on the right way? Caps installed the right way? Negative is on the outside edge on all three of those caps.
 
Here's a few pics of the caps I put on.
 

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Caps are installed right. Ohm out all 4 fuses in the bottom of the cab and check the fuse holders. Check 5vdc across cap C3 and make sure you have a good 5v there.
 
Found out the issue. One of the wires from the monitors transformer became lose at the solder joint and was tapping the transformer. Somehow when that happen the shock traveled up the wires and blew both 5 amp fuses. I soldered the wire back, reflowed every connection, and put in some fresh fuses and it's now playing. Except that crappy hum bar is still there. Damn that thing.

Thanks everyone for the help.
 
Check to make sure that you have a good earth ground running through your power cord. My Ms. Pac had a broken off ground pin on the power cable. Replacing the end with a good ground, fixed the hum bar.
 
Make sure your edge connection on the board and on wiring harness aren't burned.
 
Sorry, guess I should of put my fix up here. I replaced the isolation transformer and swapped in a new power supply after that the hum bar went away.
 
pac man hum bar

pacs are bad about this ,you probably didnt need to replace transformer,etc... dirty fuse blocks cause this. trust me ive had this issue a many times.
 
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