G07 - Gray screen

TVsIan

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I've got a Ms. Pac-Man cocktail with a 19" G07 (I think - the chassis appears to match the pictures) that cut out on me.

The backstory - the machine worked, then went into storage for a few years after I moved and had no place to put it. When it came back inside, it did show a picture, but not the whole display and with a lot of space between each pixel.

I was able to get it converged by tweaking the adjustments, but the image had a vertical (well, horizontal from the monitor's perspective) roll that I couldn't get to stop. I didn't have the time or money to do anything with it at that point, so it stayed indoors and unplugged but unused for another couple of years.

I just tried it out again today, and all I get is a dull gray screen. I can see the burn-in (which I can't when it's powered off), and I can hear the game if I try to play it, but there's nothing coming up on the screen. Also a faint burning smell, but I'm pretty sure that was just the dust burning off the light bulbs.

I don't see any damage to the flyback or any blown caps. There's a label stuck to the chassis saying "Good caps" dated 1998, so something was done to it or tested back then (a couple of years before I bought it, I think).

Looking around, I found some troubleshooting info, but not for this particular symptom. The tube is definitely getting some kind of power, but that appears to be it. And having never worked on monitors or anything high voltage before, I'm hesitant to start poking around with a multimeter without narrowing it down first.

Any pointers on where to begin with something like this? If it makes a difference, I did install a Multi-Pac kit years ago, but since that's a daughterboard to the original it shouldn't affect the video output, and it had been working until it went into storage.
 
Well since you can hear it play, you have determined that it is indeed a monitor issue.

If you aren't inclined to work on it, you should send the chassis out for repair.

I suppose you could confirm that the molex pins from the harness are connected to the monitor, if that is disconnected you could get a blank screen.
 
Well since you can hear it play, you have determined that it is indeed a monitor issue.

If you aren't inclined to work on it, you should send the chassis out for repair.

I suppose you could confirm that the molex pins from the harness are connected to the monitor, if that is disconnected you could get a blank screen.

I don't mind working on it, I'm just skittish about disconnecting the chassis after reading about the high voltage on the tube. I may wind up just getting a kit and going for it though.
 
Youtube should have some good videos on discharging a monitor tube.

Once you pull the chassis shows us a few pics on here.
 
What you are experiencing is called raster - the tube has power to it and lights up. So, you have raster but no video. The lack of video could be a simple disconnected connection from the PCB to the monitor, the PCB failing to send video or the monitor could be failing.

Here is a great website with Pacman troubleshooting info I found super helpful when I started in the hobby - http://lawnmowerman.rotheblog.com/
This website and youtube videos is also super helpful in learning about general arcade repair - https://www.arcaderepairtips.com/

In troubleshooting Pacs I always look at the fuses and edge connector first since they are known problems. Like Tronguy said if the game is playing blind then you can mostly concentrate on the monitor. Caps that were good in the 90's probably aren't anymore! G07 is a very simple chassis to learn how to do a cap kit on, or you can pull it and send it to one of a dozen guys here that do repairs. Pulling a chassis is not super difficult and you don't have to worry too much about killing yourself by electrocution.

Good luck!
 
I did take another look just now to make sure the video cable wasn't unplugged, and comparing what I can see of my monitor to a pic, it appears the width coil is broken (pic attached). I feel like that would probably explain what I was seeing before it went out entirely.

Hopefully this weekend I'll have a chance to get a discharge tool assembled and get the chassis out so I can see the parts of the board hiding under the tube and poke around with a multimeter. If I can't find anything obviously wrong aside from that coil, good to know I can send it out for repairs too.
 

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Full rebuild time.

That width coil is NOT your issue.

It needs to be addressed, but it didn't cause your problem.
 
Thanks for the help on this one. Once I get it pulled out and get a closer look at it, I'll have to decide if I want to do it myself or send it off.
 
First think I would try, is unplug and plug everything back in. Probably something just came loose.

Still a good idea to get a kit from arcadepartsandrepair.com
 
Your gray screen is most likely caused by a bad X303 or C107 on the neck board.

As stated before it is time for a complete rebuild. That will include a new flyback, cap kit, FR401, R908, and horizontal width coil. I would also get the pot kits for the G07.

When replacing the flyback make sure to be really careful removing and replacing the flyback. That are of the board is very fragile from heat and will crack.

Ed
 
Your gray screen is most likely caused by a bad X303 or C107 on the neck board.

As stated before it is time for a complete rebuild. That will include a new flyback, cap kit, FR401, R908, and horizontal width coil. I would also get the pot kits for the G07.

When replacing the flyback make sure to be really careful removing and replacing the flyback. That are of the board is very fragile from heat and will crack.

Ed

I happened to find your info in another post before you posted here and shot you an email this morning - I might be interested in getting that done instead of attempting it myself, if you're offering that repair.
 
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