Les - The low noise advantage quoted for these antennas is due to the low
sidelobes in the patttern. They will not do anything to reduce the noise seen
by the main lobe of the antenna.
I am not sure what antennas you are running now, but look at the patterns of
your antennas and the patterns of the Loop Fed Yagis and see how much different
they are. If the sidelobes on your antenna are substantially greater than the
Loop Fed Yagi, you might see some advantage.
I say might, because the sidelobes of an antenna are affected by materials in
their fields, and if close stacked, by the other antennas in the stack. I
suspect that the Loop Fed Yagis would perform similarly to the antennas you
already have in the environment you have them in.
The Loop Fed Yagis are not unique in the low sidelobe aspect. YU7EF and DK7ZB
have also designed Yagis with low sidelobes and you might find it interesting
to compare the patterns of antennas that have the length you are interested in.
Although the patterns will be different in details, they all have pretty low
sidelobes and good, if not great, front to back.
Good modern Yagis from many commercial companies are designed to have low
sidelobes as well.
In short, I doubt that you would see significant improvement in signal to noise
ratio in going from your current antennas to the new antennas, unless the
antennas you have are pretty bad. Going to a longer antenna may help, if you
can fit one in it, but if I recall correctly you have pretty much as long an
antenna as you can swing.
The increased bandwidth won't help much, most antennas tuned for the weak
signal end of the band are wide enough.
Let us know how things work out. - Duffey
--
KK6MC
James Duffey
Cedar Crest NM
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