LG 42PG3000 - no priming glow, bad buffer board

[tom66]

I found a bad buffer IC, but it's not badly shorted, only 300 ohms to output. It's bad enough to get hot though, and bring down Vsc and -Vy. New buffer is about £14 on eBay.

Early, first gen IPM-free LG plasma, 42 inches. Plus a 46 inch PZ82 (more on that later... that's a nice one...)

Video:
https://www.youtube.com/watch?v=Iw0_...ature=youtu.be

[zx81]

Re: LG 42PG3000 - no priming glow, bad buffer board

Another informative video.

Thanks for posting Tom.

[tom66]

Re: LG 42PG3000 - no priming glow, bad buffer board

Buffer replaced, TV working now. Unfortunately panel presents with a 1pix vertical line far right of image, very faint but visible. Non repairable.

That's my 2nd bad plasma panel compared to probably 10 LCD panels, at least...

[Shinju]

Re: LG 42PG3000 - no priming glow, bad buffer board

Bummer, nothing like taking time to work on something to find out it's still going to die, but atleast you got good parts!

tom66 back when I posted the panasonic plasma with the line down the screen I wasn't trying to question you I was just trying to be optimistic!

Accept my apology your input is greatly appreciated and I meant no disrespect!

[tom66]

Re: LG 42PG3000 - no priming glow, bad buffer board

It's still watchable (the line is faint and varies depending on colour), but I won't be able to sell it for much.
It appears to me like the blue and green subpixels have shorted, because when green is shown, the line is gone. Very odd. almost like it's the actual glass rather than the COF chip.

[vinceroger69]

Re: LG 42PG3000 - no priming glow, bad buffer board

pity it has this fault would you make more selling the boards seperatly? as you know there tested good. a question tom when you sell boards on ebay do you get many returns as in ive got a few that are good but i dont want to sell them to people who just want to eliminate faulty boards in there sets when theres nothing wrong with the ones im selling. if you sell yours do you offer a full refund? with buyer to pay return postage ive got some to put on but not sure if its worth the hassel.

[tom66]

Re: LG 42PG3000 - no priming glow, bad buffer board

I don't sell boards on eBay because of the issues with returns. If a TV is to be scrapped I'll sell it whole.

[tom66]

Re: LG 42PG3000 - no priming glow, bad buffer board

Pictures of the line for anyone that's interested. Luckily only paid £31 for this plus £17 for Y-buffer so can make money back selling it with minor defect. At least the problems usually don't get worse on plasmas. Just bad luck if it happens, most common on LG & Samsung, rare on Panasonic.

Adjusting Va made no difference to line prominance, though this set only has a range of 57~63V. If you adjust Va below 57V, TV will not power up. (I'm guessing a sequencing detect fault...)

[vinceroger69]

Re: LG 42PG3000 - no priming glow, bad buffer board

ive seen worse and people still watch them and it does not seem to bother them, im sure you will still make a little profit on it as you say its only a minor defect.