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[TowerTalk] True or Not True?

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Subject: [TowerTalk] True or Not True?
From: W8JI@contesting.com (Tom Rauch)
Date: Sun, 2 Sep 2001 13:50:52 -0400
> The papers are saying that the primary radiation on a dipole come from
> the middle (the high current point) AND the ends.

With a half-wave dipole...some radiation comes from near the outer 
ends, because obviously there is some current at the ends. Most 
of the radiation comes from the middle, however, since most of the 
current is there.

EM radiation comes from charge acceleration....nothing else. We 
can't have EM radiation without charges to accelerate, and they 
have to be real charges...not "fictitious" current like displacement 
current.

Maxwell had it right, so did Kraus and every book down to the 
ARRL Antenna Handbook. The highest current areas radiate the 
most. It all comes down to ampere-feet.

This is why when we make current as uniform as possible over a 
the largest possible large in-line area (and in-phase at all points in 
space around the conductor) you have maximum radiation 
resistance. It matters not a single bit what the voltage is, we only 
need that voltage to cause the actual charges to move. 

The only place we find it any different is where people are trying to 
sell snake oil antennas.
73, Tom W8JI
W8JI@contesting.com 

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