Wells U2000 - Did a cap kit, now screen is black and clicking sound

makamusement

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Wells U2000 - Did a cap kit, now screen is black and clicking sound

Had a Wells U2000 in a Cruisin Exotica. Was having a bit of a color issue, so decided to do the cap kit. Did all the caps, triple checked the positive and negative before reinstalling and all are correct. Reinstalled and now the screen is black and there is a clicking coming from the back somewhere. Cant tell exactly where. Any ideas? Clicking wasn't there before the cap kit.
 
just from handling the chassis can cause cold solder / lifted traces and broken solder. reflow a the solder on the chassis and check your work to make sure there is continuity between traces.
 
yup those chassis can be a PAIN to fix.

as suggested look over ALL your work.

give the chassis and neck board a good re-flow, they suffer BADLY from cold solder joints.

check your H.O.T. to see if it has a short.
if it does, remove it and test out of circuit.

you can use my video to help you.


if you need parts i have them.

if you don't find any problems and hit a brick wall your welcome to send it in.

let us know what you find.

Peace
Buffett
 
ALL of them are.

Peace
Buffett
1) I was sure about the first and World, but wasnt sure about Exotica.

2) if you knew that, you should have caught the error. (J/K)

There are some differences between the 2000 and 5000 as far as troubleshooting. I have a big repair log on these somewhere here that might have something relevant.
 
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the notion that you can fix a "color issue" with a cap kit though...

I know Buffett says otherwise, but if the electron gun emissions in the tube are crap, you're not going to fix it through any work in the chassis itself. I'm certain all the U5000s were built with Zenith tubes around the time their quality took a severe plunge. the K7400/7500 used them too, but WG started branching out into other tube manufacturers then, namely Philips, Samsung, and even Hitachi.

if you're inexperienced at this sort of thing I would guess you probably bridged some pads or if your tools aren't up to snuff, you could've killed a pad/trace somewhere.

this is where the Ed West method of isolating the power supply would be helpful. ;)
 
It IS possible to fix color issues with a cap kit because the color signals go through some 10uf25v caps on the neckboard and if they are going bad you'll get color problems. It's also possible the contrast and brightness circuits can be affected. And if the 12v circuit gets affected it can cause the drive transistors to not drive a color properly.

But I agree it won't fix the tube if the tube is bad.

There are other things like R811 that can cause color to drop out, the little transistors on the neckboard, the neckboard IC, etc.

This particular problem seems to be rebuild related and either the HOT is now blown (If you changed it, did you put the insulator on?) or you have a shorted somewhere that is simulating a blown HOT.
 
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I would like to point out that the "clicking" is prob your hv shutting down. It seems that you may have put an improper part in. If you have Mis-identified your board or put a part in wrong or the wrong part, you will have issue. As others have said, reflow basically everything. And double and triple check your work. Then check your voltages. Clicking can also be your flyback but it doesn't seem as that is your issue.
 
It IS possible to fix color issues with a cap kit because the color signals go through some 10uf25v caps on the neckboard and if they are going bad you'll get color problems. It's also possible the contrast and brightness circuits can be affected. And if the 12v circuit gets affected it can cause the drive transistors to not drive a color properly.

But I agree it won't fix the tube if the tube is bad.

There are other things like R811 that can cause color to drop out, the little transistors on the neckboard, the neckboard IC, etc.

This particular problem seems to be rebuild related and either the HOT is now blown (If you changed it, did you put the insulator on?) or you have a shorted somewhere that is simulating a blown HOT.

what I mean by it is it's not going to affect the emissions from the guns. if your red looks orange for instance, but it's vibrant and doesn't look brown, yes, caps will fix that. Nintendo monitors and K7000s particularly benefit in the colors from caps, I won't dispute that.

there's a lot of things with repairs that are almost second nature to me now that *I* can notice but a lot of other people can't. I only meant strictly in the CRT itself, nothing to do with the chassis circuitry.

I'm also thorough. I don't feel that monitor repairs need to be judged as speedruns. do it right the first time and you won't have the mental anguish later.
 
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