On Fri, 18 Nov 2005 23:06:03 -0500, John Popelish
wrote:

Ken Scharf wrote:
I was looking at some power supply circuits for
tube linears and was thinking about the full wave
voltage doubler. This is basicly two half wave
rectifiers in series. Now I could build this
circuit with a choke input filter for each half
wave rectifier of the voltage doubler, and I could
put the chokes in the lead without the rectifier.
In this case I could use one choke for both halfs
of the voltage doubler. The output should then
be about .9 * rms input voltage * 2
or 1.8 times the rms voltage of the transformer.

Has anybody ever tried this?

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Crude schematic showing transformer secondary
diodes filter choke and capacitors.

If the choke is directly in series with the transformer, it will have
to pass AC, and that won't provide normal choke input filtering (which
steadies the DC current after the rectifier), but just puts an
impedance between the transformer and the doubler.

All chokes are in series with the transformer and pass some AC
component. If they only passed DC we would need them.

Without giving this too much (likely enought) thought I think this
will fail because without loads across -each- filter cap, the critical
inductance will not be obtained.

There may be a way to incorporate an inductor into a doubler, but I
don't think this is it.