Folks,
I already have my top guys of phillystran. On top is currently an A3S with 40m
add on at 92'. I am planning on replacing that with a TH6 at 90' and a Hygain
402BA 10' above it. I can probably get the spacing to 12', but much more is
going to be a bit more problematic on the existing tower. Any comments on the
spacing? Is it enough? Modeling data?
I checked the archives and found some pretty good hits. I see comments from
K3ND in 1999 about a slight shift in TH6 SWR on 15m with a 402CD at 10'
spacing. K1ZM also comments about a TH6 and 402CD being fine at 10' spacing in
1999 when discussing the then new XM240. Sam Ferris tried both a 402BA and
XM240 with 6' spacing and the booms perpendicular in 1998.
I played around in NEC4WIN, but don't trust results using full sized antennas.
I would love to read more recent comments and possibly some modeling work.
--
73 es God Bless de KK1L...ron rossi(kk1l@arrl.net) <><
QTH: Jericho, Vermont
My page: http://www.qsl.net/kk1l
>>>Pete Smith said:
> At 07:50 AM 6/25/02 -0400, Saul Abrams wrote:
> >I replaced the first two 27 foot sections with Philly and the
> >clover leaf disappeared.
>
>
> For what it's worth, another supporting anecdote. I have a Force 12
> EF-240S, at 104 feet, on a Rohn 25 tower with top guys at about the 95-foot
> level. Originally, I had 21-foot semi-rigid fiberglass insulators starting
> at the tower, and then one-piece steel guys to ground level. I didn't
> notice any SWR perturbations, but the antenna didn't seem particularly
> directive, nor did it perform well in contests. I replaced my top guys
> with Phillystran, and the antenna came to life. this seems to indicate
> that even 25-30-foot spacing away from guy wires may not suffice on 40m.
>
>
> 73, Pete N4ZR
>
> Check out the World HF
> Contest Station Database at
> www.pvrc.org
>
>
>
>
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