I read the text (see below) and wondered if anyone had
experimented with a DK9SQ graphite-embedded telescoping
mast as a vertical reflector?
Or does the embedded graphite not possess sufficient
reflective density?
Just wondered ...
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http://www.io.com/~n5fc/dk9sq.html
I selected the DK9SQ mast over a similar (and $20 cheaper) mast sold by
MFJ Enterprises, the MFJ-1910, because it was said to be better
reinforced and sturdier. What I did not anticipate as a side-effect of
the composition, was the effect that the graphite might exert on the
antenna. This became apparent when I first used the DK9SQ mast to
support a vertical wire. I originally wrapped the 33 foot wire loosely
around the mast, so that my "vertical" would not be flopping around in
the wind. Big mistake. Turns out the black graphite (or whatever) in the
fiberglas rod is quite RF absorbent. On 20 and 15 meters, I could see a
2-3 S-unit decrease in received signal strength with the wire wrapped
around the pole. And I wasn't getting out well at all, getting S2 signal
reports from my Elecraft K1. But angled away from the pole (with the
wire unwrapped and about 3 feet offset at the bottom), everything was
hunky-dorey. Now I'm suddenly getting S7 reports... much better. It took
me about 2-1/2 hours to realize what was going on. So keep that in mind,
when using the mast. This certainly wouldn't be an issue with a dipole
or loop that stands away from the mast, nor should it normally be an
issue with feedline.
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--
Thanks! & 73,
doc, KD4E
... somewhere in FL
URL: bibleseven (dot) com
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