Ahhhh! So there does seem to be a mis interpretation of the formula
here.-Steve

Bill,
I believe you are placing the dependant and independent variables in the
wrong place. The Xl is the dependant variable. Xl *depends upon* F and L,
not the other way around. That is, given an L and F you calculate the X.
X is the answer.
Only if you know there are no other contributing factors can the formula
be used the other way, because it does not factor them (the parasitic
capacitance) in. That is, Given an X measurement you can not tell the
inductance, only the *equivalent total* inductive reactance.


--
Steve N, K,9
d, c. i


"Bill Turner" wrote in message
...
On 08 Dec 2003 20:09:43 GMT, (Avery Fineman) wrote:

INDUCTANCE doesn't change over frequency

__________________________________________________ _______

I maintain it does. Otherwise the formula X=2piFL is invalid. Is that
what you're saying?

I understand what you're saying about the inductance of a coil being
fixed and the reactance is the net result of that fixed inductance plus
the effect of the parasitic capacitance between windings, vs frequency,
of course. If one chooses to *model* a coil that way, I have no
objection. You will no doubt arrive at the correct reactance for a
given frequency.

The disagreement here seems to depend on how one defines what inductance
is. I maintain that inductance of a coil is nothing more than the
reactance divided by 2piF, as derived from the formula above. Do you
disagree with that? That formula has been taught for decades. Are you
saying it is wrong?

--
Bill, W6WRT