Help with dead WG monitor

[genk]

Hello,

I'm looking for a little guidance with fixing a monitor.  It is a 25 inch Wells Gardner ( I believe it's a U2000, the chassis looks exactly like http://www.homearcade.org/BBBB/mon19.jpg )  I've been told that the horizontal output transistor needs replacing.  It just makes a ticking noise when powered on.  Does anyone know a place online where I can order this part.  Is it just a matter of desoldering the old one out, and putting the new one in?

Thanks in advance..

-Genk

[Ken Layton]

If you have a U-2000 you're going to need to order a couple of special repair kits direct from Wells-Gardner's parts department. Other parts can be bought straight from Bob Roberts' site (the one you found the picture on).

Shoot me an email at KLayton888@aol.com and I'll send you a copy of my repair guide for this model. It is written in Microsoft WORKS format.

[Karetaker]

I don't have any U2000, but I have a bunch of U5000 which is it's ugly brother. As far as I know, the boards look extremely similar (and looking at the picture of the U2000 I can't see a difference). You may have a U5000. But, either way the monitor is in protect. These boards can be a troubleshooting nightmare. If it is just the HOT then yes, you can just de-solder it and put a new one in. Even if the HOT is bad it may have other component failures. I buy my components at a local store, so I can't help with buying online. I don't know if the U2000 HOT is the same(I'm pretty sure it is), but the U5000 HOT is a C3686 (it may be listed as a 2SC3686... same thing). I buy mostly NTE parts. It crosses to an NTE2324. If you have a U5000 you may want to stock up on these if you plan on keeping it.

[Karetaker]

One more thing..... When you are testing it make sure that you put the chassis screws back in. Ground is critical on these monitors! So much so that one of the modification that I've done to all of mine is to add an extra ground plug to the chassis board. On the U5000 there is a nice place to access the ground between the flyback and R122. WG was even kind enough to mark it as ground (GND). Call me Paranoid, but I've worked on a bunch of these.

[genk]

It could be a U5000,  I haven't been able to determine that yet.

What happened was that I was putting the control PCB back in it's little "holder" when it must have gotten to close to  one of the screws in the cabinet.  I saw a small spark...

Could this be more than just the HOT?   

Thanks again for your help.

-Genk

[Ken Layton]

A U-2000 is standard resolution only. A U-5000 is switchable Medium res-Standard Res by moving a jumper wire. Generally a U 5000 was kept strictly with medium res games. The 2000 and 5000 are so close that the same special repair kits from Wells-Gardner works on both models.

[Karetaker]

So he could easily identify it. A U5000 has 15 & 25k plug marked CN15K & CN25K....and the U2000 doesn't.

genk.... I would take Ken up on his offer to email you his "repair guide" for it. If you get bored in the mean time, I always check"D106 A, B, & C. D105, D107 and R104. I'd also check and go over the solders on the flyback while you have it out of the game.

[genk]

Ok, I looked and it is definately a U2000.  I'm just wondering,  would it be possible to use this chassis http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=6178761215   
with my tube?

This is the third time I've had this monitor take a crap on me, and I just don't have the skills to fix it myself.  To send it off again and get it fixed... if that chassis on eBay would work, it'd be about the same $$.  Is there a cheaper chassis which would be more reliable to swap out? 

[Ken Layton]

That chassis is a good one for the k7000 series. You have a U-2000 which is a completely different animal.

The k7000 requires an isolation transformer as does the replacement chassis on ebay. The U-2000 does not use an isolation transformer.

If you wanted to use this chassis you'd need to buy & install an isolation transformer. The vertical winding of the yoke in your U-2000 would need to be a low impedance type so you must check the resistance on the green & yellow wires of the yoke to see if it's between 9 and 15 ohms. Then you need to look at the picture tube socket to see if it's 10 pins (probably is).

[genk]

How do you measure the vertical impedance?

[genk]

Do I check the resistance from the end of the green wire to the end of the yellow wire?  Right now I'm getting zero resistance.  I don't think I'm doing this right.

[Ken Layton]

Set your multimeter on it's lowest DC resistance scale. Now stick one meter probe in the green wire and the other meter probe in the yellow wire.

[genk]

Am I doing this right? 
Is that 6 ohms then?

Thanks again for your help. 

[genk]

Anyone?

[Ken Layton]

Looks right.