[Lowfer] Counterpoise Ants

[Bill Ashlock]

Hi Peter,

>I remember Les used a counterpoise as a alternate for an more extensive
>ground system of buried radials and compromise to the yard, I believe.
>So how did that work for him and what was it compared to, a few ground
>radials and a fence? Someone may remember.

At one time Les had a CP (counterpoise) installed over his swimming pool. 
Needless to say this was a 'winter-only' setup <G>. His latest antenna was 
mounted next to his house and he installed a CP, of sorts, under his rear 
deck. I think his pool CP was a big improvement over his original buried, 
simpler, ground system and the new location performed almost as well as the 
pool CP.

>On the theory of a CP, I believe it like the antenna proper must be
>insulated from non resonate objects, eg, the ground itself. Then is it
>also a factor of how high this element of the ant. is wrt to ground?

Just a small distance above ground is required.

>And is the effective ant. height that above it, not merely from the >ground 
>base if that's the mounting position?

The effective height is based on the length and distribution of current in 
the vertical element, not the height above ground, so the CP height 
subtracts from the actual height.

>Also how do the number of radials compare from those when buried to
>those in CP?

About the same.

>Broadcast standards usually call for 120 radials at, what,
>a quarter wave long. So ours are always a compromise by that std. But
>generally four are too few and 30-40 a much nicer to have.

Agree. Remember, the 1/4WL Broadcast requirement is mostly based on the need 
to cover the area where the strong electric field exists to prevent it from 
entering the lossy ground (same as the much shorter Lowfer antenna) and this 
relates to the height of the antenna (typically 1/4WL).

Bill

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