Thread: Antenna future
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Old January 16th 04, 08:49 PM
Gene Fuller
 
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Cecil,

I am not Tom, but I will respond anyhow.

It is so hard to keep up with you. This entire thread started a few days ago
with a debate between you and Roy. You chastised Roy for considering the net
current instead of the individual components. Now you have switched back to
talking about net currents resulting from the addition of individual phasor
currents.

Which one do you want to talk about?

It is unlikely that anyone reading this newsgroup is confused regarding the back
and forth nature of the current on a thin wire. To insinuate such is merely a
cheap shot that appears intended to intimidate. (Go ahead, take your best shot.)
8-)

The concept of phasors is a common and useful tool for visualization and some
elementary numerical solutions. The simple standing wave analysis currently
under discussion and debate is certainly an appropriate subject for phasor
treatment. However, once outside of the realm of ideal one-dimensional systems
the use of phasors gets much more complicated. The use of conventional
mathematics for such problems is pretty standard.

The typical equation describing a standing wave is:

I = A * sin (kx) sin (wt)

The spatial phase of this equation is "kx", while the temporal phase is "wt". At
no time do these phases suddenly reverse direction. The resulting value for I
ranges through positive and negative values, and again it is unlikely that
anyone is confused.

If you choose to call the switch from current flow in the positive direction to
the negative direction a 180 degree phase shift, so be it. I prefer to keep the
phase in its place and let the sine function do its thing to reverse the value
of the equation.

73,
Gene
W4SZ


Cecil Moore wrote:

Tdonaly wrote:

(P.S. Art, I hope you don't equate disagreement with ridicule. I
reserve all my
ridicule for Cecil since he can take it.)



.... .. .... ..


Tom, I notice you have not posted your calculations for
the phase angles of those superposed phasors I presented
yesterday. Did you come up with any phase angle other
than zero and 180 degrees? Do you understand why Kraus'
phase graph for standing wave current contains only two
possible values of phase?
--
73, Cecil, W5DXP