Winston wrote:
The inductance of that coil fell significantly when you lopped
off the 'I' core, yes?

Can you place a small value sense resistor in series with the
'common' line to your coil? The way I misunderstand magnetic
core saturation is that we expect a 'knee' where current begins
to increase in a nonlinear fashion in relation to applied
voltage. You could set your 'scope up as an X-Y display to
show this nonlinearity very clearly.

Okay, now that caught my attention, as I've been looking for a way to
"notice" saturation when driving the primary of a MOT.

I do know that one can view phase angle with an x-y viewing of current and
voltage, and I guess it makes sense to look at that same waveform for a
change as an indicator of saturation (when phase angle is changed due to an
increase of non-inductive current).

Thanks Winston, I'm gonna have to play around with this.

Jon