Ms Pacman board issues

eefilms

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I recently picked up a Ms Pacman that isn't working. Currently the game won't boot and all I get is a low tone through the speaker and a bunch of white, scrambled text on the monitor. I've attached two pictures of the issue, the first is what I was originally experiencing (prior to putting some pressure on each chip) and the second is what I'm currently dealing with.

I am new to collecting and would really appreciate any input you all might have. Thanks.

(I'm looking to do a full restore on this cab so once I get it functional I will be posting pictures of the process in the restore section for those interested).
 

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I would hook up another monitor or put a cap kit in that one first. Make sure you use proper safety when working on CRT monitors.
The screen is likely telling you an error message you can lookup in the ms pac man manual 2-7 or it is in endless reboot...z80 chips, or freeze dip switch #7 and #8 should be OFF.

I would re-seat and clean the socketed chips after I could clearly see the monitor picture.
 
Thanks for the feedback. I'm hoping to pull the board later today so I can re-seat the chips, clean the edge connector, and pray for an easy fix...

What makes you think that it is a monitor issue too? I'm not saying you're wrong (because I have no idea), just curious where that thought comes from.
 
The screen looks really washed out. It may just be as simple as adjusting the focus but it probably needs a recap.
 
On my lunch I took out the board so I could clean it up and reseat the socketed chips. It turns out that 6E and 6H had some pretty bad corrosion on a few pins to the point that after they were removed, I barely touched them and the pin fell off (one was dangling after removal).

Does anyone have a good recommendation for where I can pick up some replacements and start there?
 
It looks like a pin broke off inside the socket when it was removed, anyone have any advice for removing it? To had no luck with the tweezers I have.
 
It looks like a pin broke off inside the socket when it was removed, anyone have any advice for removing it? To had no luck with the tweezers I have.

Just stick a sacrificial chip in the socket, then pull it out. The busted leg should come out with it.
 
Received my new chips (big thanks to Riptor!) but unfortunately still having the same issue. It looks like my edge connector may be burnt but I'm not positive (it may be blatantly apparent to some of you). I'll post pics in the morning.

I really appreciate all the help so far.
 
I had some burn marks on one of my Ms. Pac PCB's edge connectors too... It was giving the game Hum Bars on the screen... I cleaned the edge connector with an eraser (on the tip of a pencil) and I haven't seen the Hum bars since!
 
Here are some pics of what I'm dealing with. I'm assuming the original edge connector had burns so they "fixed it" but now I may have more burn?

I cleaned the current edges but didn't help much, still the same garbage and hum through the speaker. I'm leaning towards sending my board out for an exchange, thoughts on that?
 

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Finally got around to putting my multimeter on my PCB and I'm not getting continuity on the Z80A (U4). Through some research it looks like these can be the root of quite a few problems.

I'm thinking of picking up a new Z80 and see how that goes. Thoughts/feelings?
 
I've seen a few pac/ms pac pcb's with bad z80s that look similar to the pics you posted...prob not a bad idea to replace it. They are cheap. You have another working board with a z80 in it? Barrow it and test it in your non-working board.
 
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