With antennas that low, I think the biggest influence is the vehicle and
not the take off angle. It may be completely wrong, but I always
pictured it as the vehicle in the near field coupling with the antenna,
and creating considerable loss.
At some "minimum" point above the vehicle, this loss is reduced to
negligible level. From Jon's, W0ZQ /R, data, it would seem that height
for 6 meters would be around 21 feet. Actual numbers would depend on
the band involved, and the antenna.
All of this is my opinion based on my experience and anecdotal
evidence. I'm a Rover, not a scientist:-) Your points per mile may vary!
73
Dan
--
K9ZF /R no budget Rover ***QRP-l #1269
Check out the Rover Resource Page at: <http://www.qsl.net/n9rla>
List Administrator for: InHam+grid-loc+ham-books
Ask me how to join the Indiana Ham Mailing list!
Bill Olson wrote:
> In real life, at K1WHS, I seem to remember having problem working rovers with
> low antennas (7-10ft) on 6M, and they nearly always had a drop off in front
> of them.. I guess what I'm saying is, over a, say, 200 mile path, with the
> same rover, there didn't seem to be much difference if he was on flat ground
> or overlooking a cliff.. the signal was still a lot weaker than we thought it
> should be.. I guess we really need some testing here.. Guess I'll do that in
> June and report back...
>
> bill, K1DY
>
>
>
>
>
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