> Although I could not quantify the pattern for each of the
methods, I can tell you this: The TA-33 will radiate poorly
in any direction it is pointed. As far as I was concerned
the TA-33 could have been a dipole or even a high 50 ohm
resistor because it did not radiate very well with any of
the feed point methods.>>
I'm a little puzzled by that. I always wonder if there are
inconsistencies in construction or installation, or if it
just how feel about antennas that make them work or not work
for us.
There is a similar topic going on about an equipment review,
where a reviewer felt a receiver worked better and heard
things another one would not but he actually never A-B
tested the equipment. As a matter of fact, one of his
comments was that he seemed to think he was bothered by QRM
more with the new rig but only because it was a better rig.
Hmmm. The radio was expensive. He "thought" people bothered
it more. That must be because it hears better, and so it
hears QRM better too.
Some people pay to have PIN diodes in receivers changed and
swear they hear a difference, when the change cannot be
measured in any way. If you blindfold a person and ask them
to pick the radio with the good diodes, 50% of the time they
pick the stock radio.
I'm into similar things with a G5RV. They have such a sour
reputation that some people make extraordinary claims about
how poor they are. Models and measurements clearly show the
loss is only in the order of 1dB, yet you'll find an
occasional person who swears huge differences. As an
example, a certain 5 claims he measured 20dB loss in a G5RV
on 75 meters.
I did an A-B test with a G5RV and a dipole, both installed
at similar heights, and no one could tell the difference as
long as I didn't tell them which antenna was which. As a
matter of fact when I would call the dipole a G5RV and the
G5RV a dipole, the actual G5RV (being called a dipole) got
significantly better reports than the dipole (being called a
G5RV).
I thought the entire thing was pretty weird but very
interesting, because I'm sure everyone was trying to be
objective and honest.
I do know I have found a few TA33's with traps wound totally
wrong. Like the G5RV, many TA33's are thrown into incredibly
poor situations. Back porch mounts, TV masts, 30 foot towers
in a nest of wires, and so on. I remember a fellow in Toledo
who had maybe 20 antennas in a 100-ft by 100-ft area, and
would judge all these antennas with authority of how well
they worked. Imagine the pattern of his antennas!
I had a TA-33SR and it consistently tied a 2-element quad a
friend had. We horse raced constantly, so it wasn't one
report. It was absolutely better than a dipole I had. I had
a vertical above the TA33, and the TA33 beat it by about 5
dB all the time. The TA33 had maybe 15-25dB F/B. When I
replaced the TA33 with a 4-element Wilson monobander, the
Wilson beat the vertical by about 6-7dB all the time.
When I measure ESR and model trap loss in a TA33, it fits
with maybe a dB total loss.
Then on the other hand we have antennas with easily
documented high loss that people just love.
Oh well, one of the great mysteries of radio.
73 Tom
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