Author Topic: Dumpster 50" LG plasma  (Read 2228 times)

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Offline tom66

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Dumpster 50" LG plasma
« on: March 08, 2015, 07:19:40 pm »

It's a bad panel. The drivers for the panel electrodes are failed but like on the Panasonic panel you had they're bonded to the glass. This is pretty much the only fault you can't fix on a plasma (the other one being impact damage.)

The drivers are basically ~256/384 channels of 70V CMOS buffer, they convert the highspeed LVDS from the panel controller to the 70V address drive. They operate at something like 4MHz and get HOT, at least on these old panels. The flicker is probably because the panel is on "cinema" or "energysave" mode, this improves the per-frame picture quality but at the expense of increased flicker. Most panels let you turn this off (but they usually hide the option away, you'll have to look for it.)

Offline German_EE

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Re: Dumpster 50" LG plasma
« Reply #1 on: March 09, 2015, 07:46:12 pm »
Before you do a teardown or just scrap it check carefully for loose connections and/or intermittents in the thin flex connections at the side of the plasma panel. There are a few people who have repaired sets by jamming silicone rubber tubing at the right point to maintain a connection.

This is for an LCD set but the principle is the same:
Should you find yourself in a chronically leaking boat, energy devoted to changing vessels is likely to be more productive than energy devoted to patching leaks.

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