MOT power supply ??

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "J. B. Weazle McCreath by way of Terry Fritz <twftesla-at-uswest-dot-net>" <weazle-at-hurontel.on.ca>


Hello all & Henry,

I'm confused about Henry's description and diagram of the MOT voltage
doubler power supply that he's using with his Tesla coil.

It doesn't look like any voltage doubler circuit that I've ever seen
in my years of toying with electronics.  I've checked numerous ARRL
publications, and my collection of electronic texts and I just can't
see how that circuit works as a voltage doubler.

The most common circuit that I'm familiar with consists of two diodes
in series which are in turn paralleled with two capacitors in series.
The D.C. is drawn from across the diodes/caps with the A.C. applied
at the junction of the two diodes for one leg and the junction of
the two caps for the other.  See my rather crude ASCII art below.

                    --------------------------------------0 Pos. out.
                    |                  |
                    |                  |
                    -                  -
                    -  Cap             ^  Diode
                    |                  |
     A.C. in 0------|                  |------0 A.C. in
                    |                  |
                    -                  -
                    -  Cap             ^  Diode
                    |                  |
                    |                  |
                    --------------------------------------0 Neg. out

In Henry's circuit are the cores, which in reality represent the center
tap of the two seriesed secondaries, connected to anything?  At the
least I would expect the cores to be grounded for safety.

Please clue me in as to how his circuit works, as I just don't get it!


73, Weazle, VE3EAR/VE3WZL

Listening: 147.030+ and 442.075+
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