Building a 51 mhz inverted V - feedpoint question....Help!
When I first moved into my 3rd floor (top floor) apartment 11 months ago,
I wanted to get back on HF ASAP. So, I rounded up all the wire I had and
made a 153'4" dipole with an SO-239 chassis mount at the feedpoint. I
strung the antenna around this red brick building and was on the air with
my FT-817 and LDG Z-11 tuner in no time. The antenna tuned easily even
down to 1.8 mhz but I was running a straight piece of rg-58 coax from the
feedpoint to the tuner and I was getting a lot of RF in the shack.
I posed this problem to this group and was told to coil several turns of
coax at the feedpoint. I looked around for a form and found a 2-3/4"
diameter
glue bottle. I wound 9 turns of the existing coax around this form, then
used
superglue to hold the turns together. Came out rather nice and worked very
well!
A few months later I was told I might get better results with more turns on
a
larger form. I grabbed another spare coax piece and this time used a CD
50 pack round case for a form (5-1/4" dia, 12 turns). This worked even
better!
In April I finally got permission to put an antenna or support no higher
than
10 feet high on the roof of this apartment building as long as I did no
permanent
changes. I used a Rat Shack vent pipe mount and 2 - 5 foot masts to hold up
the top of a Van Gorden 134' "All Bander" antenna. Nice landlord, eh?
With the All Bander in place and after several weeks of comparing
performance
of it with the old antenna, I took down the old antenna and wrapped it up
and
threw it in the closet. Now, I'm running a FT-857D and a LDG Z-100 tuner.
I thought I'd like to build a 6 meter SSB/CW inverted V dipole out of the
leftovers from the old antenna/coil/coax setup in the closet. No sweat but I
am
concerned if that a 2-3/4 inch, 9 turn choke would be ok on 50-51 mhz at
50w?
I'm too impatient to wait so I'm gonna start building now but I 'd very much
like to hear your opinions - I can always make changes and even build more
coax assemblies with coils wound on one end with different turn diameters
and more or less turns as I have several coax assemblies in the closet that
are'nt
getting used right now.
Anyone have an opinion for # of turns and what diameter would be best for
50w @ 50-51 mhz SSB/CW? BTW the antenna will be taped to a large
window on the 3rd floor, facing east & about 3-4' from my PC and radio gear.
73's de Ken KG0WX, Denver Area, Colorado.
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