[Amps] Thoughts on half-wave dipole

[Jim Brown]

On Sun, 27 Jul 2008 20:10:42 +0100, Dr. David Kirkby wrote:

>I wish to know if the reactance of a dipole that is physically 0.5000 
>wavelengths in length depends on the diameter of the wire or not.

So study a book on antennas! It is very well known (not far from the 
beginning of the discussion in almost any text) that the physical length of a 
resonant conductor depends on its cross section. There are many excellent 
texts on antennas, including the one by Kraus. The ARRL Antenna Book is also 
quite good. Both are widely available new and used. And yes, it is quite far 
off topic for this list. 

This sure sounds like a troll, but for a hot minute, let's pretend that it 
isn't. :) 

The confusion here is between a wavelength in air (or free space) and a 
wavelength in the conductor that makes up the antenna. When we decide how 
long the antenna should be, we're concerned with the wavelength in that 
conductor, not the wavelength in free space. When we design for the spacing 
between elements of a parasitic array (like a Yagi), we are concerned with 
the wavelength in free space. 

73,

Jim K9YC