--- In FT817@y..., "KQ6XA" <xtalradio@a...> wrote:
Well, Julian, do you think maybe we should continue this discussion
on
a more appropriate forum like HFpack?
I don't think all the members of this group are members of HFpack,
and some of them may be interested in reading the thread to its
completion.
But, the my main point is this:
Especially for QRP (like the FT817), it is important not to waste
power by delivering that power into the resistive earth soil ground.
HF grounded-radial quarterwave verticals simply are not as
efficient
as elevated groundplane verticals or vertical dipoles. The old
theories about the HF benefit of buried ground radials have fallen
down under real world testing.
What this implies, at least to me, is the counterpoise is acting not
as a ground plane but as a radiating element. Actually I suspected
that might be happening, and it would explain why the adjustment and
positioning of the counterpoise is so touchy. It might be interesting
to see what results could be achieved by a full size dipole with
*both* elements lying on the ground. It might prove/disprove the
argument of those who claim the ATX is little better than a dummy
load.
I live in an area of the most conductive soil in North America
(salt
marsh island---25metres from salt water). I have tested both
grounded
radials and elevated radial verticals here (portable, pedestrian,
and
fixed antennas). The elevated ones always win by 6~20dB, depending
on
frequency and configuration.
Yes, my own elevated radial trapped vertical is many dB better than
the ATX. But then the vertical element is a lot bigger.
Julian, G4ILO
