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1/4 Wave Theories - Trash Them!




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From:  Barton B. Anderson [SMTP:mopar-at-uswest-dot-net]
Sent:  Tuesday, June 09, 1998 1:34 AM
To:  Tesla List
Subject:  Re: 1/4 Wave Theories - Trash Them!

To Terry and all,

Tesla List wrote:

> ----------
> From:  terryf-at-verinet-dot-com [SMTP:terryf-at-verinet-dot-com]
> Sent:  Monday, June 01, 1998 9:08 PM
> To:  Tesla List
> Subject:  Re: 1/4 Wave Theories - Trash Them!
>

<snip>

> Power(rms) = Vmax * Imax * COS(phase angle) * 1/SQRT(2)  Remember that even
> though the current and voltage may be high, if they are 90 degrees out of
> phase the real power is zero.

Yes, I fully agree!  V and I are 90 out.<snip>

> >comparing *phase* of current at the base and top of a coil
> >with a net reactance of 0, will *not* produce a phase variation.
>
> The reactance is not zero.  It is  2 * pi * F0 * L  or  1 / (2 * pi * C)
> The reactance controls the currents and voltages in the system given the
> initial stored energy.

Terry,

When I said above "a net reactance", I was talking about the situation when XL=XC.
Because both are opposing and opposite, these reactances cancel. If XL = 24ohms,
then Xc = 24ohms (at resonance), but, if they are opposing and opposite (of which we
know this is true) isn't this net reactance "0"? and all that would remain is the dc
resistance of the coil?

I know I must be missing something here, I'm just not sure what and am hoping you or
someone can clear me up on this point. This is why I was thinking there should be no
phase variation (at resonance). I'm not in anyway trying to prove 1/4wave theory
(since I obviously don't know it that well), nor am I playing devils advocate, I'm
just trying to understand what I obvioulsy don't. I think the above situation is
what is making me question the phase in this particular current measurement.

BTW, many many thanks for your replies. I've been contemplating yours and the rest
of the lists postings on this topic. There's so much unknown (not measured anyway)!
One thing that is certain to me, to validate tests, parallel tests of measurements
must be made including different methods of measurements. I hope everyone capable
will join in to help confirm, document, and speed up this process.

My very best,
Bart