On Tuesday, February 14, 2017 at 2:42:48 AM UTC-5, wrote:
A local bar & grill has several tv's. One of them is really screwed up,
and I wish they would either fix it, replace it, or not turn it on. It's
a modern flat screen probably HDTV. I'm guessing its a 32 or 36 inch.

The right side of the picture is normal, and has a perfect picture. The
sound works fine, but the left half of the screen is constantly
flashing, which I find very annoying. Sometimes that left side has a
normal picture for a few seconds, other times it's black, and most of
the time it just flashes.

I play around with old tube type electronics and some early transistor
stuff. I know very little about this new stuff. My guess is some sort of
a loose connection, or flaky capacitor or maybe a chip, or ????

An old CRT tv would fail either horizontal or vertical, or not work at
all. But this half screen has me puzzled. Do these new TVs have separate
circuits for each half of the screen?

No, I dont plan to try to fix it or do anything about it, except I have
asked the business owner to shut it off a few times, since there are 2
more TVs in there anyhow, and that flashing actually makes me dizzy
after awhile. But I am curious how or why it's doing this.... Can anyone
explain it???

(it's NOT the cable, since the othrer tvs work fine and are on the same
cable tv service).

It could be the ribbon cable from the TCON to the display, or even the tcon, but it sounds like a classic case of "Windex Syndrome".

Most TVs made these last few years have the display installed upside down in order to locate the connections of the display a bit closer to the main board to save some fraction of cost in copper.

Problem is the address board (part of and bonded to the display) is susceptible to any liquid that is sprayed on the screen and drips below the mask. Slowly, sometimes weeks or months after being dosed with cleaner, the address board corrodes and begins to fail. Nothing will stop it except removing all contamination. The problem is that once symptoms are noticed, it's too late. The board suffers copper leaching and the bonding between the ribbons and display fail.