Hello Tod and all,
As Wayne K8LEE mention, there is not enough RX antennas (also TX antennas).
This is because we take into consideration only the azimuth angle but less the
elevation. Ofcourse there is a simple explanation. On such a low frequency, to
have a controllable elevation beam is not for amateurs.
Is like on EME. If you have elevation, you can work EME beyond moon rise/set.
Otherwise, just look to the others.
If you have an INVV for example, signals coming between 90 to 45 degrees
(elevation) will be within 1dB range but the one from low angles, 11 degrees,
will be 10dB less. One with 1KW "sound" like one with 100W.
On the other hand, with a vertical antenna, signals coming from 90 degrees
elevation will be heard with 35dB or more less intensity comparing with an
INVV. For sure, this could be a "to be or not to be" situation.
And there is more. The noise...Noise could be assimilated being formed by all
the other signals apart from the useful one (the DX station for example).
If the noise doesn't exist than the noise floor will be close to zero
(theoretically). Useful signal could be infinitely amplified to be readable.
As all of us knows, in the real world there is always noise. If the antenna has
a very narrow azimuth/elevation beam than its noise floor (noise temperature)
will be very less, close to the theoretical margin. But in this case, that beam
should be directed to the desired signal.
That's why, "there are not enough RX antennas ever on 160m".
Solution does exist but are beyond amateurs budget.
Hope this help to understand the whole RX antenna picture, especially for
beginners on this list.
73 de YO3FFF
Cristi
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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