WG U5000 Width problem

[slots]

I have a 25" U5000 that I can't adjust the horizontal width. The coil does nothing but i do have some adjustment with the remote board. Screen is about 1 1/2" short on each side. I've replaced the width coil and Q710 with no change. Any ideas?

 

[modessitt]

The coil isn't meant to be adjusted. Have you capped it and inspected it for cold solder yet?

 

[slots]

Yep. All caps replaced and reflowed all headers including the Std. / Med. res jumper in the center of the board.

 

[modessitt]

Does it do the same thing in both standard and medium res?

Fixing to go eat, so i'll look into this more when I get back...

 

[slots]

Only tried Medium res. I have the chassis out now. I'm going take another look at the 700 section later. I'll try Std. res when I put it back in.

 

[slots]

Just tried it in Std. Res. and it fills the whole screen. Problem is only in Medium res.

 

[slots]

Ok. It will fill the screen is std res.(triple image). In med res it is 1 1/2" short on both sides. Went all through the 700 section and changed c719 & L701. So I repair another U5000 chassis and still have the same problem. It has to be a yoke problem. But why only med res.? Can I change the value of c719 to make the width wider? C719 is .27 200v mylar. I tried the .89 200v from C722 in the C719 position and the image was more narrow.

 

[modessitt]

Got any U2000's or K7400's? They use the same yoke, and you could through the chassis on it to see if it still does it with a different yoke...

 

[slots]

Got any U2000's or K7400's? They use the same yoke, and you could through the chassis on it to see if it still does it with a different yoke...

I have another machine with a U5000 but I can't get to it right now. Is the yoke in the attached picture for a U5000 (ohm readings are 7.4 & 1.4)? It came with a U5000 chassis but looks nothing like the yoke on the monitor. Also can these 25" chassis be tested on a 27" tube? I have a extra 27" u5000 tube.

 

[modessitt]

You can test it on a 27" tube, but the picture will be messed up without the pincushion board.

There should be a label on the yoke that says 9A2388-1 (or some other number). If the two yokes have the same label, then they are the same...

 

[slots]

Im' going to try to get to my other U5000 this weekend. There is no tag on either yoke but the picture tube is a WGEC 088x0387-001. It looks like that tube was used on K7000 and K7400 monitors. It's a bonded yoke (readings are 5.7 & 1.9).

Any easy way to remove a bonded yoke?

 

[modessitt]

Im' going to try to get to my other U5000 this weekend. There is no tag on either yoke but the picture tube is a WGEC 088x0387-001. It looks like that tube was used on K7000 and K7400 monitors. It's a bonded yoke (readings are 5.7 & 1.9).

Any easy way to remove a bonded yoke?

Bust the tube...

 

[slots]

Bust the tube...

Good one Steve.

I think I'm going to just swap in another 25" tube and put the other yoke on it. That way I won't ruin any good parts.

 

[slots]

It's fixed it was the wrong yoke and it was a 110 degree tube. I got to my other game with a U5000 and the yoke was the same as my extra and the tube was 100 degree. So I put the yoke on a extra 25" 100 degree tube swaped it over and it now has a great picture.

 

[coinopper]

I have one of these chassis with the same width problem. Just noticed there's no cap at C719 but a resistor next to it (R762) is burnt up.