William Sommerwerck wrote:
"Jo - the girl" wrote in message
...

Do TVs emit some sort of high frequency sound when they're turned on?

Sure do. You're hearing vibrations from the horizontal output transformer.
The frequency is 15734.25 Hz.

Women tend to have better HF hearing than men, and everyone's HF hearing
gets worse as they get older. I used to be able to hear to 20kHz or so, but
can now only hear to around 14kHz.


15 or so years ago, some manufacturers quit putting power indicators on
TV sets. For the life of me, I don't know why. It sometimes leads me
to turn the set on and off--then on again--because I saw no indication
that the switch press had any effect before the crt ramped up.

I wonder how much was saved in omitting one led...and how much extra
wear and tear on the set was caused by multiple power cycles on each use.

jak