those with extensive CRT repair experience (edit: please, for the love of sweet jebus, don't reply if you are just guessing and haven't worked on a tube)
i picked up this Sony KV-8AD11 a while ago and it has been sitting on the repair pile. while i've recapped and restored a couple of dozen arcade & tube tv's, diagnosis isn't my strong suit.
what's causing the green hue running along the left side? it remains there even after the chassis has warmed up, and switching between RF and composite input makes no difference.
interestingly, the green hue does not show up on snow/static screens. is this something adjustable via the internal potentiometers, or will it require some PCB work?
@vga256 If the symptom goes away when you remove the input, that rules out problems with the tube (non-uniform magnetization, purity maladjustment).
Do you have a test pattern generator? That'd help show the issue more clearly.
Not sure what inputs this has (RF, composite, maybe s-video?) -- do you get the same symptom across multiple inputs?
The fact that it's happening on the left side suggests that voltage is leaking from the horizontal deflection into the green color amp/driver(s). The fact that you have good colors everywhere else probably means the green channel is working okay, but is getting biased by current ending up in there when it shouldn't.
@ieure as described in the post, the problem replicates across both RF and composite inputs (which are the only two this particular trinitron has). i can probably generate a test pattern, but i suspect it'll reproduce exactly what we're seeing.
re: horiz deflection - that's exactly the kind of diagnosis I needed. i'll start with troubleshooting the H deflection circuit. thank you!
@vga256 Ah, sorry, I missed the bit about the inputs.
The real puzzler is not seeing it without a signal applied. Sweep happens the same with or without a signal, and the static is amplified noise that passes through the RF stages, so I'd really expect to see it there, too.
I wonder if it's present, but very hard to see due to the rapid movement and high contrast. I could see the white of the snow overwhelming the more mild green bias that's evident.
@ieure that's certainly possible - i was wondering if the amount of contrast in a b/w signal was obscuring or eliminating the problem. i also wondered if the fact that the noise is purely black/white has anything to do with it.
either way, the H deflection circuit is going to be my first stop.
@vga256
Magnetic deflection error, most likely due to alignment/adjustment issues, rather than busted parts. That's the good news. Bad is it might be obscure to adjust.
If you can find a repair manual, of if the design is generic enough you can probably adjust it with the right tools (generally those little plastic jobbies that look like swizzle sticks. They're often called that!)
High voltage adjacent but not high voltage itself.
@vga256 "By nose" a thing like that sometime means the tube got magnetized. As someone suggested a good degaussing could maybe help ? I suppose you need some special tool for doing it ?
@gilesgoat that's certainly possible. the part i find confusing is that the tube does not produce the hue on snow screens, which you would expect if it was gaussed.
@vga256 Then another "theory by nose" could be some of the RGB amplifier(s) with some component ( capacitor ? or transistor ? ) going dodgy ( in the need of replacement ) that when some signal goes over a certain threshold for X time amplifies in a wrong way ?
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