ANNOYING Television Noise

[Shawn Ryder]

This is my first post - but would like to become more active here!

I have a 27" RCA television that is about a year and a half old with
an RCA Receiver, DVD and of course VCR.

About seven months ago there started a noise that has become more
annoying over time - so looking for a solution.

It occurs after the television has been on for about a half hour once
warmed up. The sound is honestly tough to describe - not humming, not
buzzing, not snapping, not whistle - but present. Sometimes it does go
away but will come back eventually...

I had thougt it may be the receiver but with that off it still makes
the noise. I had speakers close to the television and moved them away,
no change. It isn't the speakers on the set, but sounds more like
coming from inside the set and an electrically issue.

Not sure if there is much that I can do but looking for some advice on
how we can correct this!

 

[LASERandDVDfan]

About seven months ago there started a noise that has become more

annoying over time - so looking for a solution.

Sounds like a high frequency ringing? - Reinhart

 

[Art]

Come from the speakers, from rear of the set, with sound on or sound
off.???? ??
Post responses with appropriate model and chassis number of your tele.

 

[Shawn Ryder]

Sounds like a high frequency ringing? - Reinhart

THAT could be a good way to describe the noise.

 

[Sam Goldwasser]

THAT could be a good way to describe the noise.

My guess would be a drying up bypass capacitor.

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[Mark D. Zacharias]

Maybe the input line filter ringing, or the horizontal drive transformer, or
even the deflection yoke buzzing. Sometimes an application of silicon or
RTV, well placed, will fix the problem.

Mark Z .

 

[Shawn Ryder]

Come from the speakers, from rear of the set, with sound on or sound
off.???? ??
Post responses with appropriate model and chassis number of your tele.

It sounds like it comes from the 'rear' of the set - doesn't matter if
the sound is on or off (muted).

 

[Li Gangyi]

probably the flyback and maybe a SMPSU trafo ringing...try some silicon
around these parts...

 

[Jerry Greenberg]

In TV sets, and various electronic devices, I have seen where bypass
capacitors were starting to go high in their ESR to cause this effect.
I have also seen situations where reactive devices, such as switching
driven transformers and reactive devices cause some ringing with age.

It would be best to have the set properly checked by someone who is
very experienced with these types of problems, in case there are
components starting to fail. If there is a failure, other damage can
result.

Jerry G.
========

 

[Cougercat]

If the sound is a high tone, very high in fact about 15 khz, your problem
might be in the "fly back transformer." The 2 core pieces might be loose.
It could be the transistor accociated with the generation of the high
voltage. Either way, it probley needs replacement.

 

[b]

seen this various times. Look in the vicinity of the line output
transformer for a coil about 2 inches high with a ferrite core.
chances are it is vibrating in sympathy with the LOPT scan frequency.
Adding a blob of silicone adhesive to the top of the ferrite core
solved all such problems I have seen
Ben

 

[NeonHomer]

I have the same problem with my 19" RCA. It is a CTC175A (I believe).
I had to replace the tuner IC (the common failure one) on this unit
about 2 yrs ago, and it has been running good since I fixed it.

Drying up cap?