My old TV used to make a high pitched noise which other people said they couldn't hear.
I have been told previously thatthis can be cuased on CRT displays when the EHT transformer (Extra High Tension?) is faulty. Is this correct?
Can this occur on LCD displays?
Since I got rid of my tv, I have not had a single migraine. I was suffering these almost every day. Could that have been a factor in why I got them?
2007-01-07 03:45:54 · 4 answers · asked by footynutguy 4 in Consumer Electronics ➔ Other - Electronics
The high pitched whistle that you can hear when the tv is switched on is at 15.625kHz . This is the frequency of the line scan (left to right of the screen) timebase. This occors in all CRT screens, though some are louder than others.
This is nicely inside the human hearing range, though some older people can't hear it.
LCD won't have this noise as it is purely electonic switching of the individual pixels on the screen rather than magnetically deflecting 3 electron beams.
If your migranes have gone, great! The TV could have caused them with the constant whistling noise.
2007-01-08 05:02:13 · answer #1 · answered by Lennyzero 2 · 1⤊ 0⤋
Humans can generally hear sounds with frequencies between 20 Hz and 20 kHz. I would guess that the sound coming from your old CRT TV was up around the top of this range.
2007-01-07 09:25:34 · answer #2 · answered by ricky_stubbs2000 1 · 0⤊ 0⤋
The answer about the frequency is 350Mhz i think.
and yh that could be the factor.
Have a look at this website ... Hope it helps
http://en.allexperts.com/q/Macs-Apples-1506/iMac-CRT-display.htm
2007-01-07 03:51:00 · answer #3 · answered by Ash S 2 · 0⤊ 2⤋