Hi Jim,
Looking back at my notations The Double Bozooka noise floor was a needle width
less than the folded dipole on the OMNI VI Plus on 17M.
A lower S meter reading, when only noise is present, could be an
indication that the antenna actually somehow responds less to noise,
while working equally well (compared to the other antenna) on signals.
It could also be an indication that the antenna has more loss than the
one you are comparing it to. If the two antennas you are comparing have
essentially the same geometry, that is they span the same distance from
end point to end point, and have a feed point in the same location, then
there is a real good chance that the one with lower noise power at the
receiver also has lower signal power at the receiver, due to higher losses.
On the lower HF bands, there is usually enough atmospheric noise being
picked up by your antenna (unless it is really, really inefficient) to
overcome your receiver's noise floor (unless your receiver has a really
high noise floor or overall low gain). As long as atmospheric noise is
greater than your receiver's noise floor, you don't lose any receive
capability due to the losses of the antenna. It's the guy at the other
end that will have less signal from you due to your antenna loss, who
may not hear you above the atmospheric and other noise. He might not be
able to hear you tell him how good your SWR is.
Maybe because of my location which is not NOT a IDEAL situation, the Double Bazooka worked better for me on 17M for what ever reason. I challenge any one to put one of these up and compare it side by side to another wire antenna and see what happens.
That is a problem in antenna comparisons. Two side by side antennas do
not act independently. They will interact. You would have to take one
down while you test the other. Even if the one not being tested was
laying below on the ground, it would likely have an effect on the
overall performance of the one in the air. Since you cannot keep band
conditions constant long enough to lower one antenna and raise the
other, the test effectively cannot be done, unless the noise sources and
signal sources are all non-skywave .
DE N6KB
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