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A belated s.s. realization



Original poster: "K. C. Herrick by way of Terry Fritz <teslalist-at-qwest-dot-net>" <kchdlh-at-juno-dot-com>

Those of you who have paid attention to my "current-ring" s.s. primary
design may want to read this.  As you will recall, I employ two loops of
primary conductor connected together with energy-storage capacitors.
Each loop incorporates multiple switch-transistors and each set of
transistors acts alternately with the other set to pass current from the
capacitors unidirectionally through first one loop, then the other, thus
setting up the alternating magnetic field that excites the secondary.

Each transistor is protected against reverse--and excess forward--voltage
by the "catch" diode that is connected across its opposite transistor, by
coupling via the associated energy-storage capacitors.  But there lies
the rub.  It appears that the circuit is a bit like the proverbial bee:
unable to fly according to known aerodynamic principles, it flies anyway
since it does not know that.

When one of the sets of transistors is conducting, all is fine: current
flows in a "daisy chain" through the transistors, the primary conductors
and the storage capacitors, setting up that direction of primary-current.
  But then, when that set of transistors shuts off at the end of its
half-cycle and the other set becomes turned on, each transistor of the
other set finds that it is paralleled by a catch-diode that is mightily
conducting in its forward direction, catching the inductive overshoot of
the opposite set of primary conductors.  That forward direction of diode
conduction places a low voltage of the wrong polarity across each
transistor that at that moment is supposed to begin conducting.
So--those transistors do not begin conducting and the circuit doesn't
"fly".

Except...it does fly; or at least, is has been doing so.  So those of you
who may have been considering use of a similar configuration, take heed.
While I take 5, likely a lot more than 5, trying to figure out a) why it
has worked at all and b) how to change it so that it works
understandably.

Ken Herrick