What is going on with my T.V?
Five minutes after I switch it on it starts squealing like a potato in the microwave. The pitch gets higher and higher and every time I think that this might be the day it explodes and shoots slithers of bloodthirsty glass into my rosy-red cheeks.
But then it just stops squealing and acts like a normal T.V should.
The whole thing only lasts for about a minute or so but it seems longer when a programme I really want to watch is on. If ‘Will & Grace’ was on I might be asking how to go about extending the duration of the squeal but as it’s only on once a week I guess that would be like shooting myself in the foot.
This has happened to pretty much every T.V I have owned.
So whats going on? Is it getting ready to take off but then notices the window is closed so it puts off all escape plans till another day? I mean if it really wants to go out the window it should try getting stuck on Channel 4 when ‘Will & Grace’ is on.
This is a telling statement. You’re probably hearing flyback noise from the magnetic coils at the yoke of the picture tube. I’m lead to think that it’s not that your TVs makes that noise m ore than normal but that you have exceptional hearing for high frequencies. Not everyone can hear flyback noise and not everyone hears it at the same loudness as it’s outside what is considered the “normal” range of human hearing.
Check out this section of Sam W.'s repair faq.
Note that working inside a TV is not recommended. Lots of dangerous stuff even unplugged.
No, it’s within the so-called “normal” limits. Human hearing is generally said to encompass the range of 20 Hz to 20 kHz, and the horizontal circuit typically operates at about 18 kHz in the US (slightly lower in PAL countries). I do agree that this is what the OP is hearing, though it’s less likely to be sound generated in the yoke, as much as in the flyback transformer itself (which for simplicity of design operates at the horizontal sweep frequency). Presumbably there is a temperature range at which this noise becomes audible, and once it warms up sufficiently, the sound is damped.
Obviously, I haven’t heard smam’s TV myself, but I’m inclined to think otherwise. Our TV does this from time to time also, and the sound it makes is:
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High in pitch, but not that high. I can still hear flyback whine on many TVs, and this squeal seems a lot lower-pitched to me, although it’s high enough to be very piercing and unpleasant. (By the way, if it was simple flyback noise, wouldn’t the pitch remain constant at the flyback frequency, rather than rising as described?)
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Quite loud. When the TV makes this sound, everyone in the room immediately assumes that a smoke alarm is sounding - if not in the room, then somewhere nearby.
Since the TV seems to work fine in every other way, we pretty much just ignore the noise - it goes away after a minute or so when the set warms up. Ours doesn’t do this very often, but it does seem more likely to happen if the set has been off for a long time (several days) before being used.
Forget about that. From now on everyone call me ’ Exceptional Hearing Boy’
Whats that? Already I can hear many people from different countries snickering and calling my superhearo name " lame and stuff. "
Ah! Dougie from Croyden with your soft-toned discussion to your wife in the bathroom with the door closed and the toilet flushing of what my name should be I think you have hit the nail on the head, I will change my name to ’ Fear-ache ’ as it’s much more snappy, kinda limits me to the evil side of things though, but so be it.
OH NO! I can’t shut it out, take it away please I can’t stand it. Who on earth bought the box DVD ‘Will & Grace’ set? Shit! I can even hear the network tapeing new shows.
Once I destroy every box-set and W&G script I will return, to perhaps take over world or maybe just spread malicious gossip and stuff. Oh yes, you will HEAR from Fear-ache again
" Neeheheheheeeeeheeeheehcoughcough! "
We put up with this for a good year before I nearly put my foot through the screen. We finally had to get a new one. Thank jod, cuz I was “this close” to losing it!
I’m constantly hearing high pitched squealling and even moaning from from TV. Coincidently, there’s video of people having sex also on the screen…
I can hear a very high-pitched sound from my TV, but it’s not that loud. I can barely tell it’s there unless the TV is tuned to a silent channel (empty video input, VCR blue screen, etc), and then it drives me nuts.
If everyone in my house could hear it, I bet they’d remember to turn off the TV after turning off the DVD player. :grumble:
[little girl from Poltergeist]
They’re here…
[/lgfP]
IIRC, the flyback transformer frequency for NTSC (US TV standard) is 15750 Hz, a bit lower than the 18 kHz you cite. I used to hear it when I was younger, but I’m old now, so my ears aren’t as sensitive.
Yes, you’re correct. I was confusing that with the old Hercules Graphics Adapter standard of 18.43 kHz. I’ve been working on computers far too long.
Are you watching American Idol when you hear this?
Could be the fangirls.
I’ve heard this when tv sets are operating in a very damp atmosphere, or they have not been used for some time, like several months.
Its a mechanical problem.
Something is vibrating at the horiz freq.
A loose rivet or something is allowing a metal part to move and you are hearing the resultant whine.
At least thats what my TV repair instructor said.
It used to be a lot worse in the old sets where there was a lot more shielding.
It did come in handy a few times when troubleshooting.