Antennas have always remained some what of a mystery to most of us which is
probably why we like to experiment with them. It's also where we can
*sometimes* get more return for the effort and money than any where else in
the station.
Over the last 45 years I've tried a lot of different antennas from my first
inverted-V in 1961 to the current installation. Along the way I've had
big antennas and little antennas. I had them high and low and even a contest
style station with the big KLMs on separate towers.
I will add that I live 43:37N which is half way up the lower peninsula of
Michigan. That means the bands get fairly quiet for QRN this time of year.
75 and 40 are currently about S1 or S2 for background noise QRN and QRM
combined.
In the past I've noticed something quite different than others appear to
have seen when using verticals for receive particularly on 75 and 40. I
only have a half sloper on 160 which works well...OK, but I have nothing to
which I can compare. On 75 I have switchable, half wave, center fed slopers
which work very well. I have the same on 40.
On both 75 and 40 I have found that 1/4 wave verticals make very good
receiving antennas for DX most of the time. Compared to half wave dipoles
and inverted-V antennas where I could switch between the antennas without
the need to retune I found that on many occasions the lower angle of
radiation and acceptance worked to my advantage in a rather substantial way.
The antennas not only got out better on long haul but appeared to hear the
lower angle coming in a tad better. However the big difference was the
reduction of stateside QRM by about 2 S-units. Although I have one of the
100 KV plus transmission lines within half a mile and I am surrounded by
electric fences (which can be a problem at times) The verticals were able to
hear the DX much better than the horizontal. OTOH most of the time they made
rather poor stateside antennas. At times there is little if any difference
in the received signal strength of the DX station, but the "difference"
between the strength of the state side stations compared to the DX made the
DX much easier to copy.
I have found this to be true at three different locations but all were
within a 50 mile circle. The one place where I have not had any experience
with a vertical is at this location. I don't count the Hygain AV640 as much
more than a dummy load although it seems to get out on 40 and 6-meters. I'm
looking for a light weight aluminum tower (locally) that I can use on 75
this winter just for an experiment.
On one point though, over the years I can not remember ever seeing the noise
higher on the verticals than on the horizontals. That doesn't mean it
wasn't at times, but it certainly wasn't enough to stand out to where I'd
remember it.
So, my point is for those who want to try an antenna, we can give you
theory, we can give limited experience, some have substantial experience in
specific geographic areas, but for your own location the only way to find
out is to put up the antenna and try it. You may be disappointed, or you
may be pleasantly surprised. Either way it should be a healthy learning
experience.
Roger Halstead (K8RI and ARRL 40 year Life Member)
N833R - World's oldest Debonair CD-2
www.rogerhalstead.com (Use return address from home page)
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