PLEASE HELP!! i have a 32" jvc flat screen tv(not plasma), n' shortly after i turn it on, it emits a high pitch "whine" noise that's EXTREMELY unpleasent. i've noticed that the noise only stops when: if i've been playing video games (Wii) when the noise began, it stops when i turn the Wii off....... any ideas..??????? 
Does it whine audibly when you are watching regular TV or just when playing the Wii?
The only source of whine I can think of in a flatscreen TV would be the switching power supply and if that is actually the source you might want to consider replacing the set with something quieter assuming it is out of warranty - otherwise get it serviced under the warranty . (Replacing the set's power supply might or might not be a possibility out or warranty, but could cost enough to make the point moot.)
When I was in my early 20's I could hear the flyback transformer whine in most analog TV sets from 10' or more away - my purchase decision was made based on finding one that had inaudible flyback whine. Not sure you can do that in today's shopping environment for the analogous situation you seem to be describing.
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Chances are it is a lose ferrite core in one of the inductors of the power supply (I confirm above diagnosis).
If you are brave, you can open the PSU and poke the inductors / transformers with a wooden chopstick.
Use extreme caution, these power supplies have non-isolated mains on some large capacitors - hence only poke with a wood or plastic object. And touch nothing by hand while it is plugged in.
An alternative is to spray the chokes sequentially with a 'freezing spray' aerosol - bought for exactly that purpose at electronics dealers.
When you find the noisy core, douse it with silicone sealant (once the AC power has been disconnected)
There may be a separate power supply for the fluorescent backlight.
If you are brave, you can open the PSU and poke the inductors / transformers with a wooden chopstick.
Use extreme caution, these power supplies have non-isolated mains on some large capacitors - hence only poke with a wood or plastic object. And touch nothing by hand while it is plugged in.
An alternative is to spray the chokes sequentially with a 'freezing spray' aerosol - bought for exactly that purpose at electronics dealers.
When you find the noisy core, douse it with silicone sealant (once the AC power has been disconnected)
There may be a separate power supply for the fluorescent backlight.
I agree with the diagnosis above but am concerned about the guidance.
Mains switch mode supplies have arround 400v which is not current limited in any way.
This will probably kill you if you touch it.
Unless you are confident about what you are doing, can do it in an area where children cannot enter and are wearing rubber gloves. I would not advise trying to fix this yourself.
By all means have a go if you are confident but please be carefull and keep in mind one slip is all it takes.
My old boss now has a heart murmer because he wasn't carefull enough and he is a electronic engineer with a PHD from Cambridge. (He is also only about 40, any older an he would probably be dead now)
Regards,
Andrew
Mains switch mode supplies have arround 400v which is not current limited in any way.
This will probably kill you if you touch it.
Unless you are confident about what you are doing, can do it in an area where children cannot enter and are wearing rubber gloves. I would not advise trying to fix this yourself.
By all means have a go if you are confident but please be carefull and keep in mind one slip is all it takes.
My old boss now has a heart murmer because he wasn't carefull enough and he is a electronic engineer with a PHD from Cambridge. (He is also only about 40, any older an he would probably be dead now)
Regards,
Andrew
Hola Y'all...
I work on cars for a living high voltage used to be only in the ignition. Now we have hybrid cars that need servicing and we use rubber gloves with cotton glove liners rated at 1kv to service the higher voltage stuff(high amperage TOO!)...Electricity can kill it's not the volts it's the AMPS.
Good Luck Y'all, Elwood
I work on cars for a living high voltage used to be only in the ignition. Now we have hybrid cars that need servicing and we use rubber gloves with cotton glove liners rated at 1kv to service the higher voltage stuff(high amperage TOO!)...Electricity can kill it's not the volts it's the AMPS.
Good Luck Y'all, Elwood
I'm sick of hearing and reading this credo, it just trivializes the potential hazards, and IMO this is not a very responsible way of looking at the issue, at a couple of kV just a few mA flowing through the right portion of your body can kill you. It pays to be careful around any high voltage supply and the higher the voltage the more careful you should be. (True also for high current supplies at any voltage, and storage batteries of all types.) I have heard and seen enough in 30yrs of electrical engineering not to subscribe to this credo, it's a gross oversimplification that often makes people way too comfortable around extremely high voltage low current supplies. (Old color TV/computer monitor CRT flyback supplies running at 25kV+ at a couple of mA CAN kill you.)
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