Vertical on a tower
Nope. Verticals are notorious for picking up local man-made noise.
Man-made noise starts out with random polarization but the horizontal
component is quickly "shorted out" by the earth's conductivity, leaving
only the vertical polarized component. This is why AM broadcast
stations universally use vertical polarization; better groundwave
coverage. They are not concerned with skywave or local noise.
For skywave, either one works fine, but a horizontal antenna is quieter.
They don't pick up *that* much more noise. Sometimes the difference
would be fairly small. When I ran both the elevated GP, and the
dipole,
the antenna that received best, transmitted best nearly all the time.
If there were exceptions, they were so rare as not to really remember
them. If you are working long haul DX paths, the signal increase of
the vertical will override any extra noise. And the increase is almost
always higher than the increase of noise. Noise on the vertical was
never really an issue here. And I'm in the big city of Houston to boot.
When I talked to VK land using both antennas, the vertical would beat
the dipole by appx four S units. Both transmit and receive. If the
noise
came up an S unit or two, it's a non issue. When working from here
to the west coast, ditto, except the difference would be two S units
instead of four. Even in those cases, the noise was never high enough
to make the dipole the preferred receive antenna. Dunno..I think all
this "noisy on a vertical" talk is greatly overstated. Also consider
that most of my local noise here is random, and often effects both
antennas nearly equally. If you are working long DX and receive on
a low dipole, you could be robbing yourself of a lot of received signal
to be had. In my case, 4 S units worth to any long haul dx. You
telling me I'm gonna see 4 S units of extra noise? Never here at this
QTH... Maybe 1 or 2 at best. I *never* wanted to receive on my dipole
if I was working long haul off the vertical. Would be like shooting
myself in the foot.
MK
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