Do we really care that skimmers aren't hooked up to antennas with
pattern and gain? One of the things in using VOACAP is knowing the
pattern of the RX antenna as well as TX. Omni pattern at RX removes RX
antenna bias. Why shouldn't we specifically use omni on RX, so that
any enhancement is from the sender or the propagation/environment?
If I wanted to know what antenna was better, I would use a short vertical
or vertically polarized antenna for most applications.
Ideally, you want a broad elevation pattern with no nulls. A 2 foot
vertical has about the same pattern as a 130 ft vert for elevation on 160,
so the only issue is sensitivity falling into RX internal noise.
I think people live on the false notion that verticals have a null at near
zero, which patterns on Ham models will show, but that is a program
display shortfall causing that error. If they really were zero, all
broadcast stations would be dark for groundwave. :)
BC antennas have the elaborate radial system in order to get that groundwave
while the typical on ground ham vertical loses a lot of the 0-10 degree (or
more) radiation. Go to the beach to get it back.....or go with elevated
radials.
Carl
KM1H
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