Help - possible TV flyback issue

A

Avneet

Guest
Does anyone know if the flyback can cause a squeeky/whistle sort of
noise coming from within the TV. The picture and audio are perfectly
fine, speakers sound perfectly fine. This is a noise coming from
within the TV. When I switch TV to Video I, II or III, the noise is
distinguished since there is no audio on these channels.

Please respond. Thanks.
 
Avneet wrote:

Does anyone know if the flyback can cause a squeeky/whistle sort of
noise coming from within the TV. The picture and audio are perfectly
fine, speakers sound perfectly fine. This is a noise coming from
within the TV. When I switch TV to Video I, II or III, the noise is
distinguished since there is no audio on these channels.

Please respond. Thanks.
Click to expand...
It is indicative of a faulty FBT in every case

--
Peter E. Lowrie
----------------------------------------------------------
 
The transformer probably is 'faulty' the windings can be loose on the former
used to wind the transformer. Sometimes the problem can be alleviated by a
SERVICE TECHNICIAN for minimal cost, in other instances the transformer has
to be replaced. I remember a new Philips set here (NZ) that many did it
from new, Philips wished us to try and 'adjust' it before replacing it (at
their expense ;)

HTH

Warren
"Peter Lowrie" <peterlowrie@consultant.com> wrote in message
news:1638356.JfASr7Ib55@xbox.pelnet.net...
Avneet wrote:

Does anyone know if the flyback can cause a squeeky/whistle sort of
noise coming from within the TV. The picture and audio are perfectly
fine, speakers sound perfectly fine. This is a noise coming from
within the TV. When I switch TV to Video I, II or III, the noise is
distinguished since there is no audio on these channels.

Please respond. Thanks.

It is indicative of a faulty FBT in every case

--
Peter E. Lowrie
----------------------------------------------------------
Click to expand...
 
avneetsingh3@yahoo.com (Avneet) wrote in message news:<4ee60208.0312121159.387f2fea@posting.google.com>...
Does anyone know if the flyback can cause a squeeky/whistle sort of
noise coming from within the TV. The picture and audio are perfectly
fine, speakers sound perfectly fine. This is a noise coming from
within the TV. When I switch TV to Video I, II or III, the noise is
distinguished since there is no audio on these channels.
Click to expand...
I'd guess the whistle is from the line scan coil,probably about
15.625kHz for a 50 fields per second TV - particularly as the AV
channels silence it (I assume you've no video connected at that
point).

If you can find the coil,a huge blob of hot melt glue can dampen it
sufficiently,
Sprow.
 
Most any of the reactive components that are high power driven in your
monitor can cause the type of noise resonance that you are discribing.

The switching drive transformer in the supply, flyback, and deflection
yoke are some of the types of devices that can cause this. There may
be an internal winding or a few of them that are sort of loose
internaly, or the metal core of the device, or some near by piece of
metal that is resonating. The fundimental frequency of the device may
be very high, and out of the human hearing range, but the sound you
hear may be from the sub harmonics of the resonance.

This type of sound is harmless, and is normaly not to be worried
about. There are instances however where a defective component can
cause a type of audible resonance, but this is another aspect of
things, and generaly when this happens, there may be some type of
performance loss showing from it.

You can bring your set to a service center to look for the resonance,
and maybe it will be an easy fix that is not expensive. There are some
models of sets that normaly make some degree of noise.

My own TV set has some resonance noise, but I have to go very close to
the back of the set to hear it. I never took the bother to see what
the exact cause is. Most likely it is from the power supply drive
transformer or the deflection yoke by the way it sounds to me. Since
the set is working properly, I will let it be as it is.


Jerry Greenberg
http://www.zoom-one.com

--


avneetsingh3@yahoo.com (Avneet) wrote in message news:<4ee60208.0312121159.387f2fea@posting.google.com>...
Does anyone know if the flyback can cause a squeeky/whistle sort of
noise coming from within the TV. The picture and audio are perfectly
fine, speakers sound perfectly fine. This is a noise coming from
within the TV. When I switch TV to Video I, II or III, the noise is
distinguished since there is no audio on these channels.

Please respond. Thanks.
Click to expand...
 
Jerry's got the right line on this one; this is a fairly common problem in
newer sets, and it can be very difficult to totally eliminate. Usually involves
using a wooden or plastic skewer (chopstick) to lightly probe various coils and
transformaers while set is operating and "whining". Touching the offending
component will cause it to quiet down. Dab some silicone sealer or glue on the
part, let dry and test.
 
btvfxer@aol.com (BWL) wrote in message news:<20031213000717.15295.00000661@mb-m12.aol.com>...
Jerry's got the right line on this one; this is a fairly common problem in
newer sets, and it can be very difficult to totally eliminate. Usually involves
using a wooden or plastic skewer (chopstick) to lightly probe various coils and
transformaers while set is operating and "whining". Touching the offending
component will cause it to quiet down. Dab some silicone sealer or glue on the
part, let dry and test.
Click to expand...
Do not use solvent based glues on coils, they may cause the insulation to fail.
I use use heated 24HR araldite.
 
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