New Tv showing Brown spot with video

[PlatinumMOTO]

I just got a new flat screen tv it's not a flat panel though but anyway I have it split in between a 2-way splitter so that I can see what ever is on my computer screen on the tv and then into the living room and when I plug my surround sound into the tv in the living room that way I can hear the music or movie or whatever it is and I don't have tot have the surround sound in the bedroom where my computer is. But I started noticing a light brown spot
on the tv sometimes. I use an RF modulator to transmit the signal to both tv's from the computer.

and it looks fine but every now and then I notice a brown spot on the tv now I have the RF modulator on 4 ohms and not 3 ohms but it has to be on 3 ohms to be recognized from the starting up of the computer.

then I switch it to 4 ohms because it makes the picture more clean and crisp but I've tried it on 3 and 4 ohms and every now and then I see a brown spot I thought it was my phone so I don't keep it by the tv anymore but the tv still gets the spot what is it do I need to take the tv back?

[guns1inger]

Don't know it is the same thing, but the first model Loewe I bought had a similar, although more yellowish that brown, stain. If the TV was turned off, the stain went away, but soon returned. It quickly dawned on me that this issue was magnetic, as turning off the TV automatically degaussed it, the issue was finding the source. All my cables and speakers are properly shielded, and there was nothing else nearby. They replaced the TV with another of the same model, and within a few days the problem re-occurred.

Called the supplier again, and found out they had several reports of the same problem in our area. Apparently the magnetic fields in our local area reacted with the ferrite mesh in the screen. They immediately dispatched a new television - the next model up with a non-ferrite mesh - at no cost as a replacement, and I have had no problems since.

[PlatinumMOTO]

Could it be my cable modem or RF modulator causing the interference?

Does it permanently affect the tv?

[PlatinumMOTO]

I found out it's not 3 ohms and 4 it's 75K and 1K.

[redwudz]

75 ohms is the impedance of regular coax like the cable TV companies use. Not sure what the other number might be. The older flat twin lead is usually 600 ohms.

Most RF modulators work on channel 3 or channel 4 in the US. A cheap modulator may cause problems, but it's usually just interference (herringbone) lines or shadows from over-the-air TV on the same channel.

You also might want to check the quality of your splitter, though that doesn't sound like the problem.

It may or may not be the fault of the TV, it's hard to tell unless you connect the computer or a DVD player almost directly to the TV, with no long cables or other stuff in between.

[PlatinumMOTO]

it's a 75K ohm and then it says 1 and I've tried on both settings and it still shows up it's a brownish yellow spot on the right top side of the tv.

I noticed the splitter I have says 5-900MHZ does that matter I think it's a cheap one too.

[redwudz]

I have something similar to that when I watch B+W movies on my TV, though it's a green spot, about 8 inches across. I never figured out what causes it, and it doesn't show up all the time.

If your TV was doing it all the time, no matter what channel or video source, I would say it was the TV. I can't come up with any part of your system as you have described that could put a spot like that on the TV screen. The most common cause is a strong magnetic force near the TV, but you could test that by moving it. And it would not likely be brown, but one of the primary colors, red, green, blue.

That splitter is probably OK. Sorry, I can't think of anything else.

[TBoneit]

Well it sounds as if you have a CRT and they are influenced by magnetic fields.

Is there anything near the TV that could have a magnetic field? Speakers, subwoofer etc.?

[PlatinumMOTO]

The only thing that is by the tv is my monitor it's on the others side of my desk and the monitor is off I hardly ever turn it on. I moved my RF modulator and my cable modem and my phone. The printer/scannter/ copier/fax is on top of the desk and all the cords and cables are behind the desk below it.

I'm gonna buy a splitter for like 9.00 and if that doesn't fix it then I'm gonna take it back.

[Megahurts]

Since the spots are intermittent, I suspect you might have a doming problem. This occurs when bright objects are on the screen (especially if contrast/brightness are set too high) for a length of time which heats up the shadow mask causing temporary color distortion.

http://www.repairfaq.org/sam/crtfaq.htm#crtdom