Polo Monitor issues... will a cap kit fix this?

crash41301

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So I picked up an NBA Jam that had a 25" Polo monitor in it. The color is pretty washed out looking on it. I've tried adjusting it to no end. Either I had darks and no color or I have color and little darks. I've attached pictures of the best I can get the screen to adjust using the adjustments I know of; Brightness, Contrast, the 2 on the fly-back, and what I assume are the red and green gun's.(There is no blue gun knob??) I've adjusted monitors before to look great so I am confident it isn't me in this case.

Before I go to the trouble I figured I'd ask. Do you think a cap kit would help with this or is it the guns themselves and a re-juvinate is the better option?

I am aware of the issue in the top right of the picture. I am assuming some a-hole put a magnet to the thing at some time in its life. Its not too noticeable during game play so I'm hoping that if I had better color it wouldn't be noticeable at all. Maybe if I'm REALLY lucky it'll go away with a cap kit too? lol.

Lastly, the pic in the next post shows the grid lines of this monitor. As the picture goes from top to bottom it seems like the lines also get closer and closer. Would a cap kit fix that? Something else perhaps?

Appreciate the input!
 

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a cap kit would probably help out allot and should be done as a preventive measure.

but the tube could need some help as well. it may need a rejuve.

so cap it first and see where it goes.

and do you have a ac drill you can use it to degauss that spot in the tube.
do it with the glass off so you get the full power of the drill against the tube.

Peace
Buffett
 
a cap kit would probably help out allot and should be done as a preventive measure.

but the tube could need some help as well. it may need a rejuve.

so cap it first and see where it goes.

and do you have a ac drill you can use it to degauss that spot in the tube.
do it with the glass off so you get the full power of the drill against the tube.

Peace
Buffett

I would degauss and rejuve it before you cap it. Yes, cap kits are easy and cheap, but degaussing and rejuving are generally free if you have someone around with the stuff.
 
before cant hurt and after is a must.

always after as when you move the tube the earth's magnetic field will mess with it.

Peace
Buffett
 
What is an AC Drill?

Dang on the rejuve. Anyone close to local with one?

Edit: AC Drill, you dont mean an AC powered drill, like what I'd drill holes in the wall with do you?
 
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Yes

What is an AC Drill?

Dang on the rejuve. Anyone close to local with one?

Edit: AC Drill, you dont mean an AC powered drill, like what I'd drill holes in the wall with do you?

Yes In a pinch a drill can work to degauss the screen if you plan on doing it to a few monitors buy a degaussing ring they are cheap enough.
 
If you want to bring the monitor by the shop, I can hit it with the rejuvenator. Also, if you happen to need another tube (judging by the pictures, I don't think you do), I've got a couple nice ones.

Edward
 
If you want to bring the monitor by the shop, I can hit it with the rejuvenator. Also, if you happen to need another tube (judging by the pictures, I don't think you do), I've got a couple nice ones.

Edward

Sweet, PM'ing you for location and info :)
 
So Edward was awesome enough to hit my tube with his rejuve last week (Thanks again!) he also even fixed my degauss which apparently had cold solder joints on it since it fell off when he touched it. (Thanks yet again ) Per his machine the guns and tube should be ok now. The blue gun was a bit low, but the rejuve brought it back up.

I got home and installed the monitor, fired it up and adjusted away. The picture unfortunately looks similar to what it did before. Boo! So being that I didnt have any parts for it and my 4yr old REALLY wanted to play it again I decided to just adjust it as best as I could for the time being. Once it was adjusted the last thing left was to fix the vertical linearity since the bottom was a bit squished. I reached back there and adjusted the wrong knob thinking it was the right one. I ended up adjusting the X-ray knob. While watching the mirror I immediately noticed that it wasnt doing what I wanted (In fact the picture mostly whacked out) and thought "oh crap that might be the wrong knob". I wasnt really sure what position the knob was originally in so I set it back in the middle and the picture looked ok again. I then peeked around and realized where the knob I wanted actually was, I then adjusted this until I got the vertical linearity correct.

After a few minutes though the screen began whacking out again. Eventually the screen starts experiencing collapse and seems to turn on/off. Argh... I've a feeling I broke something else by turning the wrong knob! If you turn the monitor off and come back later it has a picture that looks like the attached picture.

So... fast forward a few days and the cap kit showed up at my house. I went ahead and installed them all and re-flowed the entire board hoping that might fix it. (and the color) Same thing on the screen and same behavior. Dang!

Any thoughts? Considering I am a complete newb the only thing I know is to try the hot and flyback. I've also saw mention to replacing IC101? Help is greatly appreciated.
 

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It works again! OMG what a big ordeal. I can see why people dislike this monitor chassis now :)

I ended up getting a ton of help from a fellow over at arcade controls board on this. I figured I would share here though for anyone searching in the future.

I re-capped the chassis, then shortly afterwards the entire chassis died. @*($*(&@$@!!!!

I swapped the HOT to the new (better?) HOT from mouser and installed a new flyback. That made absolutely no difference.

I found that R234, a 10 ohm flame proof resistor (that acts similar to a fuse) had lost all continuity. I put a new one in, it too popped. After alot of hassle, anger, and frustration I eventually found out that the brand new capacitor I had put into position C14 was shorted. This was causing R234 to pop since it was sending 200v directly to ground. I put a different cap into position C14 and the power started working on the monitor. The 200v going to the neck board was low though, and as a result made the picture out of whack and small. I also installed a new LM1203 IC. Nothing changed. I ended up fixing a bad solder joint a D137 (Well I think anyway?) which fixed the problem. I then was FINALLY back to the messed up color picture I had at the beginning of this thread. ie: the caps did absolutely nothing for me :(

Along the way though I learned a ridiculous amount about how CRT's work, how monitor chassis work, etc etc. This is an amazingly good video collection by Randy From I stumbled upon. I'm not sure why its not stickied in this section? http://www.youtube.com/watch?v=YsZ5PJB-w2s It would help people like me that didnt know jack about CRT's a TON.

So after watching Randy's videos, I found that my original problem was probably just a color drive transistor. I put 3 new ones in (why bother just replacing 1 when they are only like $1 a piece?) and now all of the colors work great. The monitor looks spectacular now.

This polo was my first ever attempt at fixing a monitor chassis, and OMG what a nightmare it became. It sure does look nice now though with its rejuved blue gun, new flyback, hot, cap kit, LM1203, R234 and 3 color transistors. lol

If it helps anyone in the future, here is the more detailed version of my ordeal. http://forum.arcadecontrols.com/index.php?topic=118247.0

Big thanks to the grantspain over there and good luck to anyone that works on one of these. :)
 
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