[TowerTalk] Fw: Why radials improve radiation!

[Al Williams]

----- Original Message ----- 
From: Al Williams 
To: SteppIR at yahoogroups.com 
Sent: Wednesday, May 18, 2011 8:23 AM
Subject: Why radials improve radiation!


Help, Help!
There have been many, many postings on how to set up the radials but never a discussion on why or how radials actually effect the radials as it seems to be "beyond the scope....".

It is pretty easy to understand why from a circuit current loop viewpoint i.e. the transceiver power output is divided between the radiation resistance and the ground resistance (ignoring connector, coils, and wire resistance). 

1. However the radiation resistance is a make-believe or psuedo resistance apparently derived from calculations of subtracting ground system power (system loop current x ground resistance)    from the transceiver power output. Thus, since the loop current is known and the remaining power is known, then the radiation resistance can be calculated?

But his seems analagous to lifting oneself up by pulling up on ones bootsraps!

2a. For vertical antennas, it is said that there is no reflection (radiation) from the ground system.
It isn't very clear why, horizontal or vertical polarization or ? 
2b. It is also that radiation is a result of the changing state of the electrons in a material, caused by the changing current intensity. Thus the material is acting like a capacitor (charging and discharging as the current changes. For the material to charge/discharge there must be an opposite charge/discharge somewhere?
2c. Is this "somewhere" the ground or the radials? Do the radials allow the antenna material to charge/discharge to greater amounts? Why and how?
3. If 2c is true then "heating up the ground comments" hides what is really happening?

help help

k7puc



  ----- Original Message ----- 
  From: Scott Myers 
  To: SteppIR at yahoogroups.com 
  Sent: Tuesday, May 17, 2011 5:42 AM
  Subject: [SteppIR] Re: BigIR 20 meter issue.
  snips

    I never suggest less than 32 radials for good radiation efficiency.

  As mentioned by others, resonance does not occur in ground radials, nor would you want it to. That discussion is well beyond the scope of this thread. ,

  Scott AC8DE