chirp / squeak noise ... possibly TV?

[rymik]

Hi
I have been trying to track down the source of a intermittent and very annoying chirp/squeak noise in my room. I have exhausted all possible mechanical sources (ie plumbing electrical,hvac etc) and the only other thing in the room I can think of is a 4 year old Sony LCD TV which is working fine.

Ive only noticed the intermittent noise when the TV is on. It will happen only once or twice during a 4 hour span. However, when it occurs, I cant get up fast enough to pinpoint it to the TV exactly... I just know its coming from the general area of the room where the TV is.

I was able to cut power off to the circuit once while the chirp occurred and after power was removed it still chirped for a few moments so I initially ruled out the TV. Then I realized maybe it could still make this noise since the caps haven't discharged yet?

So I was wondering...

Does a intermittent chirp/squeak from an otherwise working TV seem plausible? Failing power supply? And if so, can it occur in standbye or with power removed?

Im close to pulling my hair out so I appreciate any input.

[dick_barton]

Re: chirp / squeak noise ... possibly TV?

Do you have any other electrical appliance(s) which only switch on occasionally that the TV could be picking up electrical noise either through the air or along the in house power lines?

[Andrew F. Ali]

Re: chirp / squeak noise ... possibly TV?

Cellphone in RFI perhaps??

[rymik]

Re: chirp / squeak noise ... possibly TV?

I notice complaints online about "chirping" tv's and power supplies....(either the TX or diodes are the cause)... however, those complaints usually associate with non-working televisions.

Instead of interference, I am thinking a mechanical noise associated with power supply. However, you guys deal with broken TV's everyday and have experience in these things..... have you ever heard a working TV make squeak or chirping noises?

[RJARRRPCGP]

Re: chirp / squeak noise ... possibly TV?

I notice complaints online about "chirping" tv's and power supplies....(either the TX or diodes are the cause)... however, those complaints usually associate with non-working televisions.

Instead of interference, I am thinking a mechanical noise associated with power supply. However, you guys deal with broken TV's everyday and have experience in these things..... have you ever heard a working TV make squeak or chirping noises?

I think I heard one of the newfangled fluorescent ballasts of CFLs do that kind of thing before. It's most likely an SMPS output frequency you're hearing. (or part of a PSU with higher than utility AC frequency, which would be at least after the primary filter cap)