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Discussion Starter · #1 ·
I've got a one month old Toshiba direct view HDTV, model 34hf81. When it is turned on you can hear three or four times the soft noise apparently from relays. Then a quite loud noise which I have trouble describing, and then the picture comes up and everything is OK. Is this normal? Do ther direct view TVs do the same?


My 10 year old 20" sony did not use to be so loud on power-on.


Thanks
 

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Discussion Starter · #4 ·
Thanks for the replies, it is good to know that it's common.
 

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Quote:
Originally posted by dish in it out
You are hearing the inrush current of the inductive load created by the transformer in your power supply. A robust power supply is a good thing!
But most TV's now have switching power supplies and only your dog can hear them whine. The noise is most likely the degauss coil around the picture tube. This is typically run off the 60hz powerline and hums when energized, especially on a 36" where the coil is quite large.


The purpose of this coil is to de-magnetize the tube as stray magnetic fields attract the electron beams off the proper color phosper dots resulting in wrong colors. Even the Earth's magnetic field is enough to cause this error.
 
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