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RE: Richard Quick/flyback Xformers




Hi all,

Some of the horizontal output / flyback transformers I have
encountered, particularly on the more modern TV's has an
inbuilt voltage multiplier - rectifier (Cockcroft - Walton)
hence there is a string of diodes and capacitors between the
winding and the output terminal. Then you won't read any DC
conductivity to anywhere. These transformers tend to be
completely potted, with a rectangular section somewhere on
the housing that houses all the caps and diodes. Is your
transformer like this?

The HT  winding on these things tends to be an extension of
a winding that is used to obtain a main rail voltage in the
set - but there are exceptions to this.

So more likely than not, you could find the "other end" of
the winding by connecting to any of the pins connected to
the winding with highest resistance since this winding
typically supplies 120 - 180 V DC to the scan circuitry
of the set.

    MMMMM-MMMMMMM-MMMMMMMMMMMMMMMMMMMMMMMMM----Multiplier------ Out.
    |    |       |                              |
    |   Taps                                    |
    |-----This end, internal to multiplier------|
          connected back to start of winding

The fact a rectifier stands in the way may be bit of a bummer though.

Hope this helps,

Nick B.

><snip>
>Another thing, which is probably obvious to everyone else. I got hold of a
>flyback transformer and hoped to build a solid state coil from it. (Heavy
>duty stuff is impossible in my current accommodation!). Anyway, I ordered
>all the bits and made it, only to discover that the flyback transformer HT
>lead lacked continuity with any of the other leads on the thing!

>It serves me right for assuming everything would go okay!

>Cheers
>Phil Mason