WG K4600 in Ms. Pac washed out color

danzig8155

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I bought a Ms. Pac from a fellow Klover a few months ago. When plugged in you can see the game running but the color was really washed out...usually orange. I bought and installed a capkit from Bob Roberts, as well as replacing the 4 block fuse holder and the edge connecter. I'm out of options. I know the board works fine because I threw it into a Ms. Pac CT we have at the shop...and it's actually a Super Ms. Pac with speed chip. It played fine in the CT...so it's gotta be the monitor or the wiring...any suggestions?
 

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Also forgot...I can adjust the red, green, and blue...but when i do each individual one comes out waaaaay too much except blue. i.e. i adjust the green and it the screen is really green, i adjust the red and it's really red. The only one is blue, if I turn blue and red down all the way you can see the blue...but otherwise it's not noticeable.

And at first there seemed to be a thick solid line of color on the right hand side of the screen, but a few adjustments took that out...but now the picture jumps a twitches a little side to side just a bit.
 
Anyone know what these pins are for??

On the main board for the monitor there is a 4 pin connector by R622, by VR601 a 3 pin, by R602 a 3 pin...none of these have anything connected to them. However, the 3 pin by R602 had a female connector to it...and there were 2 black wires kind of dangling about, I could tell they came from there cos one wire had the crimped terminal on it and the other was bare (the crimped terminal was still inside the connector).

The two black wires go off to the right side of the monitor and connect to a little board with a cap and a diode i think, then go somewhere inside the monitor from the front.

Also, theres a huge 6 pin connector by C625 that I can not get to come off for anything. I'm afraid of going all Hulk on it and ripping something apart.
 
4 pin connector by R622,
by VR601 a 3 pin,
by R602 a 3 pin...none of these have anything connected to them.

Exactly.

However, the 3 pin by R602 had a female connector to it...and there were 2 black wires kind of dangling about, and connect to a little board with a cap and a diode.

That goes to your degauss coil.
 

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And you already adjusted the "black level control" (located on the video interface board) and the "Screen" control (located on the neckboard)?

Screen control is normally set at around 10 o'clock position.

Your capkit should also have included a brand new black level control to install. You did install it didn't you? If so, you also must adjust it.
 
And you already adjusted the "black level control" (located on the video interface board) and the "Screen" control (located on the neckboard)?

Screen control is normally set at around 10 o'clock position.

Your capkit should also have included a brand new black level control to install. You did install it didn't you? If so, you also must adjust it.

Hey again Ken,I was waiting for you to show up. lol Yea it came with the black level control pot...and as Bob Roberts suggested I mounted it in reverse (on the solder side) to make it easier to get to. I adjusted the black level and the screen control...the black level, if i darken it, you can barely make out any of the images, especially Ms. Pacman.

It almost seems as though the black is too black or not black enough, and the colors are waaaay too high...But when adjusting the colors it washes out the screen with whatever color your tweaking.

And there seems to be a lack of yellow for Ms. Pacman...either that or you can't see her because the screens washed out.
 
Well I tried readjusting the black and screen knobs, Like I said before...the black works..but it makes all the colors waay too dark. I have noticed though I think I have a lack of blue.

If I turn the green and red way up, it's very obvious and the screen gets washed out in those particular colors. If I turn the blue way up...the only thing noticeable with it is the highscore and 1up/2up at the top and some of the ghosts...but it doesn't wash out the screen like the others.
 
There's a possibility of bad transistors on the video interface board, but more likely your picture tube may be in need of rejuvenation.
 
Does anyone have a list of TV tubes that might work in a WG 4600? I have a similar problem, and searched some of the articles here and on the web, but there is a lot of reading to do on WG4600. I also read the discussions on the 8-liners chassis and tubes, and not sure that I want to go that route.

I have a WG 4626 chassis with a P305 interface board. Can anyone suggest a brand / model of TV that has a compatible tube? And, if you have it, what is the part number on that tube?

I did find one article on the web that indicated that showed some info, but not sure how accurate it is:

http://www.junknet.net/donor-tvs

Also, how does one measure the horizontal and vertical ohms needed on an existing tube?

Thanks for any advice you lend in advance!
 
You measure the yoke, not the tube. You put the meter leads into the ends of the yoke corresponding with either H or V and note the Ohm readings for both. Find a tube with a yoke that is VERY close to those numbers and you can keep that yoke on the tube (just need to swap the connector) and avoid converging it.

If you can't find one with a yoke that's close, but the tube is the same, you can swap the old yoke to the new tube, but you'll have to converge it.
 
You measure the yoke, not the tube. You put the meter leads into the ends of the yoke corresponding with either H or V and note the Ohm readings for both.

Yoke, yes, sorry for my bad terminology. So I have Yellow, Blue, Red, and Green wires. How do I know which is horizontal, and which is vertical? Is it a left / right pairing, or a top / bottom pairing? From what I measures, it looks like yellow and green is one correct pair, and blue and red is the other, but I didn't try every combination.

Can you confirm which are correct? See attached picture..

Thanks for your help!
 

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The coloring is standard - red/blue (H), green/yellow (V). Well, some monitors don't use this standard (G07).

Of course you could have tried metering in various combinations and would have found that out pretty quickly - red/green would be zero, as would blue/yellow.
 
I did try a few different combos yesterday, and did get a reading between yellow/blue and red/green. However, I tried again today and got nothing. I must have been touching the leads with my fingers yesterday and measured my body resistance instead.

My readings are 8.1 ohms Vertical - Green Red and 2.5 ohms Horizontal - Blue Red. That's a little off from the junknet.net readings of 2.7 HOR and 8.3 VERT. Just how close do the numbers have to be?

Also, you said that if I find a TV tube with nearly identical yoke readings, I can use that yoke and tube, but if they are off, then I would have to use my existing yoke and converge.

If I can't find a TV with similar yoke readings, then can I use roughly any tube (assuming same size, shape, crt pins, etc. with my existing yoke, or do I need to find the same tube as my existing tube?

It sounds like almost any 19" tube will work if I am willing to swap my yoke -- is that true or not? I'm guessing not, but do need to ask.

Thanks
 
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