Ms. Pac-Man cabaret-devoid of blue

[YoshiM]

Just happened to turn on Ms. Pac for some night time play (as she's been so neglected for a few weeks) and found that the blue was all but sucked out of the screen. It's set to free play, so top of the Midway logo is black. I read online that this issue could be the monitor or the "Blue output edge connector pin U is grounded." The monitor looks to be old but had a cap kit installed on it from the company that was selling it at MGC. Other than that the game works great.

Reading up it seems like the edge connectors (where I'm assuming this "pin u" is located) get dirty or burnt out. When I get a chance I'll attempt to clean it but any other suggestions would be appreciated.

[XYXZYZ]

This is Jesus' way of telling you to ditch that weird little cabaret and get a proper upright.

[edit- Billy Mitchell watercolor painting removed because even I got tired of it]
"Yoshi, ditch that weird little cabaret and get a proper upright." - Jesus


But seriously, before anyone makes any suggestions, are you handy with a soldering iron / know what you're doing with electronics?

[YoshiM]

Why does Jesus kinda look like Billy Mitchell? Besides, Jesus knows a full upright won't fit in my basement. A testicle was almost lost getting a DK JR cab down there.


I'd classify myself as a beginner. I have modded my Saturn and that works still. Haven't gone beyond that. Though I can follow directions.

[DogP]

I'd clean the edge connector and check for a bad solder joint on the video input connector on the monitor board (wiggle it and see if it comes/goes). Be careful in there though, the monitor especially has lots of high voltages. If it's not something simple like that, I'd suspect a monitor problem more than a game PCB problem, though either are possible. A quick test is to swap the blue and red pins on the cable going to the monitor and see if there's still no blue on the screen.

If you need to go deeper, we'd need to know what monitor brand/model you have (a picture of the monitor board would allow us to ID it).

DogP

[YoshiM]

I'll try the cleaning and will post pics as time allows. Thanks!

[YoshiM]

Tried cleaning the contacts but no go. The blue is still absent. I did notice that at least a couple of pins on the edge connector have been retinned. Also the connector on the main board looks slightly warped, but I'm not sure if that's shadow or what. Don't know exactly which wires to flip flop to test the colors, though.

I did take pictures but they aren't the greatest. According to labels I saw, this is what's in there: Electrohome 13" color monitor, product# 38-G07902-00 (the "0" after the G was distorted but it looked like a zero). Label elsewhere stuck on the tube confirmed that as did the manufacture dates (November of 1980 I believe).

I'll sort through the pics when I can and will post as time allows.

[jb143]

Here's a helpful flowchart...
http://www.rotheblog.com/images/arcade/misc/flowcharts/g07_flowchart.pdf

According to this it could be transistors X105, X106, or X101


And there's a spec with schematics and parts list on this site...
http://www.mikesarcade.com/arcade/monitors.html