<< In a message dated 1/10/01 7:59:44 AM
Pacific Standard Time, n4kg@juno.com writes:
<< A truly self supporting 80M vertical is a challenge.
A set of LIGHT guys, close in, greatly simplifies the
design. For relatively short masts with very small
loads, there is no reason the guys can't be spaced
very close to the mast, say 30% of the height, as
long as the vertical load does not exceed the rating
of the material. Low stretch black ropes and some
small screw anchors should do the job and be
nearly invisible from a distance.
de Tom N4KG
>>
I see 65' flag poles all over that never blow down. Every time I see
one I say "80M vertical and with no guys". If a ham wants to make
it out of welded steel joints, they will stay up with no guys with the
proper base. I have my eye on several that are not being used.
Has anyone run side by side A/B tests of a 1/4 wave vertical with
a good ground radial system vs a 1/2 wave vertical on 80/75&40M
with no radials matched with an L network and a ground rod to coil
the coax shield? Or a 1/2 wave with and without a radial system.
I compared a HyGain HyTower 75M 1/4 wave to top loading the Hy
Tower 1/4 wave to an "electrical 1/2 wave" and L network voltage
feeding it. There was no comparison with the upside down current
loop. The DX called me. Few believed I was using a HyTower. A
JA was in Seattle and came out to see it. This was written up in CQ
about 35 years ago. It was a top loaded 1/8 wave on 160M fed directly.
I plan to do it over side by side on 160M also. I have another version
using a 40' length of 3" irrigation pipe as the bottom section that is
easy to build. 4 parachute cords held it. Both were hinged at the base
and I could tip them up my self. K7GCO
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