Thanks JC,
I agree that the RDF number is significant when evaluating a receive
antenna. I agree that no one antenna system will work all of the time.
Consider we have two scenarios: One RX antenna system that consists of two
parallel antennas (Broadside) , and the other is the same antenna configured
in-line, toward the desired signal (Delayed series fed).
What I am asking is if anyone has any, on-the-air experience and would
recommend one antenna system over the other for *most conditions*. In other
words, will an antenna that has a less lower elevation pattern generally
outperform an antenna that has a narrower beam width, but a higher elevation
angle?
I think in this we need to consider the arrival angle of atmospheric noise
in a broadside array vs. atmospheric noise in a series fed array. Since
atmospheric noise propagates and the arrival angle will change, which
scenario would provide the general overall better performance?
Jim - KR9U
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Jim
RDF is everything ! The RX antenna system is the only way to improve
signal to noise ratio. All electronic device is not perfect and introduce
noise and deteriorate the signal to noise ratio, including your radio too
RDF is one way to measure directivity .
You may do not need directivity to improve signal to noise ratio if you are
operating from a very quiet location or a desert island on the pacific
without man made noise.
If you deal with noise at your location you will select the antenna with
better directivity. That's adds another component how to cover all
directions.
Better RDF equals to better signal to noise ratio.
That's is true for all bands, try to work 20 meter contest with a vertical
with 1 kW and compare with a 5 elements Yagi with 100W. Your TX signal will
be the same however for sure you will prefer to receive on the Yagi due its
directivity. You won't hear much on the vertical
Regards
JC
N4IS
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