Jim,
I had a similar anomalous propagation observation about an Off Center
Fed half wave emulating, vertical I tested. I got short skip
simultaneously on 20m SSB with long skip for a long night. With good
signals for both. Almost anything can happen in short wave radio when
the conditions are good.
Have you read the L. B. Cebik, W4RNL, web site on Bazooka Antenna
studies he did using the more powerful antenna modeling programs? His
work is very trustworthy and thorough. It agrees with long published
text book studies of fat antennas, and losses in antennas.
We all know coax is more lossy than parallel lines. Even when used in
an antenna element, coax would have a loss tangent due to the
dielectric. On the up side, it makes the antenna less long than bare
wire types. As with any antenna, there are tradeoffs.
Unfortunately, the cost per foot for Bazooka, and the wind loading are
downsides for my location.
I may try one sometime from parallel line like 450 ohm, or even make my
own wide spaced elements or cage elements of wire. That might make the
ultimate Bazooka, low loss, and low wind loading.
73,
Stuart
K5KVH
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