[TCML] Questions on the Freau SRSG Phase Controller

[A Rothman <canihazpolepig@xxxxxxxxx>]

I have a SRSG, consisting of a 1/2 HP 3450 motor, modified for synchronous
operation via the usual grinding of flats in the rotor.  The motor is
equipped with a second winding, in lieu of a run or start cap, to provide a
second phase for starting purposes.  It is switched out via a centripetal
switch after the motor spins up.

I have followed the standard schematic, but included a contactor which
isolates the variac and the motor from the capacitor when power is
withdrawn.  I have increased the resonant capacitor value from 20uF to
105uF, in 5uF increments, and have not observed the resonant rise in voltage
across the motor terminals.  What I do observe is a monotonic decrease in
that voltage, as the variac is adjusted from minimum inductance upward,
until the motor speed starts to fluctuate, accompanied by an even steeper
drop in voltage, but with 5-10V oscillation in unison with the motor's
throbbing.  As I increase the capacitance, the threshold at which the
motor's throbbing starts seems to come sooner in the variac's rotation.

Help!
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