TopBand: Re: N4KG 160 system ?

[W8JITom@aol.com]

In a message dated 97-02-02 10:47:05 EST, you write:

>N3CDR states that his 1/8th wave loaded counterpoise compairs very
>closely, signal wise, to a 10 radial system.
>
>Thanks for the space,
>
>Bill Harris...W7KXB

Hi Bill,

First a point of humor. 

I fully expect in a few years the real truth will come out.

No radials are better than 120 radials, and the less radials we use the
better our signals will be. The shorter the radials and antenna, the better
our systems will work. Truth will eventually reveal the ultimate antenna as a
loading coil and two inch stub hanging from the end of our feedlines.

After all...if there is no antenna (or ground system)..... there can be no
loss.

But now seriously, what he base that postulation on? Field strength
measurements?

As an additional comment, be careful when feeding an elevated system against
a grounded tower. Current divides at the feedpoint, with some current going
up and some (out of phase) current going down. Since common modeling programs
treat the earth connection as a perfect termination, the current going down
from the feedpoint does not cause I^2 R losses in the program.

The correct way to model that system is to insert a resistive load in series
with the base of the tower at the poibnt where it connects to ground. Here in
Georgia, a four foot deep tower base looks like 60 ohms or so of RF
dissipative resistance.

73 Tom

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