"Alan B. Pearce" wrote:

> >This is usually caused by the flyback transformer
> >windings or ferrite loosening up due to heat and
> >stress causing high frequency vibration or a
> >possible arcing.
>
> All the examples I have come across have a supersonic noise that drives me
> crazy, and it has always been because something electronic has died in the
> horizontal output stage and made the waveforms incorrect. The resulting
> incorrect waveform radiates sound from the mechanical vibration of the LOPT
> in an incorrect mode.

>
> I have yet to come across a unit where the problem has been a mechanically
> loose component.
>

Newer flybacks are dipped in a rubber compound to seal it from moisture and
vibration. Some flybacks are made up of a two piece ferrite or iron powder core
with a non ferrous (brass) long screw and nut holding them together. On a
problem unit I had, I used a long plastic tool to push on the flyback winding
or core and was able to change the whine or eliminate it altogether. Tightening
the screw a little and "glpting" the core made the fix permanent. Just remember
to remove power and discharge the 2nd anode and all associated parts.
Rick

>
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