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Old April 26th 07, 05:39 AM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
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Default Analyzing Stub Matching with Reflection Coefficients

Roy Lewallen wrote:
Once again, I request that anyone who is interested in seeing what I
wrote please look it up at groups.google.com, and not rely on Cecil's
recollection and creative interpretation of what I wrote.


I doubt that anyone is interested enough to wade through
thousands of postings so I fetched one of yours:

Current Through Coils Mar 22, 2006, 1:11 pm
Roy Lewallen, W7EL wrote:
The total current ("standing wave current" in Cecil's parlance)
certainly does have an associated phase angle, and its phasor certainly
does rotate. (By "phase" I mean time phase.) A sinusoidal traveling
current wave can be expressed as a phasor whose value is a function of
position. When you add a forward traveling wave to a reverse traveling
wave, you're adding two phasors. The result is a phasor whose value is
the vector sum of those two phasors. This is the total current. It has
magnitude and phase like any other phasor, and the same rotational speed
as its components.


The standing wave current phasor has the "same rotational speed
as its components"??? How can that be when the forward current
phasor and the reflected current phasor are rotating in opposite
directions?

Your statement above is in direct contradiction to Kraus's
graph of phase on a 1/2WL dipole where the current phase from
end to end varies away from 0 degrees by only a couple of degrees.
EZNEC agrees with Kraus. That graph is Figure 14-2 on page 464
of "Antennas for all Applications", 3rd edition. EZNEC says
the phase of the current on a 12WL dipole varies by only
two degrees over the entire antenna.

If the phase of the net current doesn't vary end to end on a
1/2WL dipole, how could you and W8JI use it to try to prove
that the phase shift through a loading coil is zero degrees?
Isn't that called assuming the proof?
--
73, Cecil http://www.w5dxp.com