Bill Turner wrote:
Both statements are true and easily provable. A simple air core coil
which measures one microhenry at a low frequency may have an inductance
of several millihenries (or even henries) when near its self resonant
frequency. It's a simple law of physics; there is no way around it.
And *above* the self-resonant frequency, the choke actually behaves like
a capacitor, believe it or not.
Now you have gone and said something that is simply not true. The
small inductor has a nearly fixed inductance with a parallel with a
nearly fixed capacitance. The combined impedance of these two fixed
reactances produces a nonlinear impedance, but there is nothing about
that impedance that implies a large change in either the inductance or
capacitance of the combination, at least not until you get to so high
a frequency that the winding is a significant fraction of a cycle
long. The rise in impedance near resonance does not exhibit the same
phase shift that between voltage and current that a large inductance
would have.
--
John Popelish
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