On 3/1/2020 7:44 PM, Don Kirk wrote:
Hi Rick,
My first example is why NVIS can be useful. I often can't hear stations
150 miles away on 160 meters using my TX vertical, but they are booming
in on my pennant that has a much better response to higher angle signals
(I could definitely generate more points in a 160 meter contest if I had
the option to switch to an NVIS TX antenna at times). We can deal with
fading, phase cancellation at times, etc. in our hobby, but in the AM
broadcast industry they want to preserve signal and audio quality as
much as possible all of the time so it's really a different situation.
73,
Don (wd8dsb)
OK, Don, that's a fair argument.
I should be able to do some simple tests on the BCB
comparing my car radio with a whip to a pocket radio
with a ferrite rod antenna. The ferrite rod antenna
is omnidirectional wrt to elevation on account of
symmetry. At sunset, the SF Bay Area stations reduce
power and become hard to hear 70 miles away here in
Sacramento county on the car radio. My Sangean radio
should pull these in a lot better. I will do some A/B'ing.
I completely agree that for 80 and 40 meter contests,
vertical miss out on all the close in stations. I
have 80 and 40 meter cloud warmers for SS, etc.
I'm just not so sure that this happens on 160 meters.
Rick N6RK
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