WG-U5000 issues

Rattanee

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So yeah... the time has come to deal with one of these again...

It came as working, but was doing the hula -really- bad.

Closer inspection after getting it:
Neckboard looks funny... remove neckboard, find plastic 'key' around the pins smashed to bits, with all the pins standing this way and that, one pin wasn't even making contact...
So... have a few of these pulled off from tubes I had to toss... while trying to put it on and straighten the pins, suddenly heard a quiet crack.... glass cracked.... thought I got away with it when I heard no noises, but at the smallest touch it began air intake... so... tube ---> hillside....

Lucky I had a spare tube from an U5000 that I got without a chassis. I bolted that in, and hooked it up. (Oddly enough the vertical yoke readings didn't match... I think there was a 6 ohm or so difference...)

Power on: monitor fires up
-doing the hula like mad
-colours are pretty much a -mess-, bias and cutoff and whatnot varies randomly, touching the pots at -all- gives disastrous results....
-picture occasionally fades out to black, then comes back. The filament voltage comes and goes as when it's black the neck glow goes aswell
-Vertical position doesn't adjust all the way, At it's lowest setting when the picture's top reaches the top of the tube, there's still an inch of blackness left at the bottom...

HULA:
Replaced C115 with a used one (don't have same rating on hand), which changed nothing... might try snagging a brand new one once stores open tomorrow...

What else is there that could cause this?

COLOURS:... yeah... need to replace all the pots.... anyone know a source for the style of pots wg used, or am I stuck using generic trimmers?

FADING:
I really truely hate WG schematics.... can anyone point me where the filament return goes to after it arrives back to the mainboard via cn201pin12 ? The rest I have looked through, pretty sure this is going to be a bad solder joint...

VERTICAL pos:
Anything common that causes this? Otherwise I guess I'll just have to start metering out the whole vertical section....


Thanks for the help folks
 
Alright... so... went ahead and put all new lytics in the smps, , result, nothing... no ticktick, just nothing...pulled it again, noticed a blob of solder landed between two pads. Removed, install, turn on, it fired right up, butthe picture was doing a large wobbling like when the degauss stays locked on... switched it on, removed degaussplug, same thing.
Plugged it in again, and lo and behod, picture is fairly stable... the remaining little wobble I'm pretty sure is because I could only get a 220uf cap for the mains filter, I'll get a 270 uf when the store restocks.

I patched upthe neckboard, installed new trimpots, colours are now fine.

Patched up all the solder pads in the filament line, the picture has not gone since...

Tube will need a rejuve as blues get washed to the side.

Problems remaining:
Cannot decrease width enough.
Vertical position does not go low enough... I'm pretty surethis is connected to the next problem
Vertical linearity is bad, bottom of the pic is shrunk compared to the top.

If anyone has any ideas, letme know... thanks...
 
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