Greetings Ladies & Gentlemen,
I claim to know very little about antenna theory. However I have noticed
something on a practical level with a new antenna and wonder if any of
you might be willing to comment on it and clarify for me what I have
observed.
I recently purchased a SteppIR variably tuned Yagi. (See page 129 of the
December QST or visit their website at www.steppir.com)
This is a three element yagi with the ability to tune each element
remotely from the shack. (Look at their website, they explain how it is
done better than I could here.)
I was listening to a fairly long winded SSB QSO last night on 20 meters
and had time to make several measurements of front to back on a loud
station. The SteppIR has a one button swapping of director and
reflector, so flipping the direction 180 degrees takes but a few
seconds.
The loud station was in North Carolina and I live on Bainbridge Island,
just west of Seattle, a distance of about 3000 miles. With the yagi
pointed at the Carolina station he was registering a solid 5 dB over S-9
with peaks to 10 dB over S-9. Flipping the director and reflector
dropped him down to barely peaking S-1. Is this really 50+ dB front to
back? The rig used was an Icom 756Pro. My yagi is at 60 feet in the
clear.
I have noticed the same kind of results on other stations, but this was
the first situation where I was able to switch back and forth numerous
times with the same results. (Thank goodness for long-winded SSB QSO's.)
I know this is not a valid scientific experiment, so please do not
attack me as if I was claiming it was. I am only reporting an antidotal
(as K7LXC would say) observation. (Is that how you spell "antidotal?)
Because this antenna is brand new to the market (and a heck of a lot of
fun to play with I might add), I thought some of you might find my
observations interesting and feel moved to comment.
Comments on this reflector always seem entertaining and sometimes
educational.
Best Wishes for a Happy Holiday Season,
Kim Bottles - K7IM
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