I have 3 TH7s stacked on a rotating Rohn 55 tower. The antennas are at
the 40', 80', and 120' levels. I used these spacings as they worked out
well on my particular tower. I put out a query about this very subject
when I was putting my array together last fall. Theoretically, a
shorter spacing distance (perhaps 32 - 36') would be more oprtimal,
particularly for f/b on 10 and 15 meters.
Unfortunately, we have not had good enough propagation on 10 meters yet
to really test the array. However, on 20 and 15, it's dynamite. It has
excellent front to back on both bands. With what little testing I've
been able to do on 10 meters, it appears to have good front to back (>
20 db) on that band as well., in spite of the fact that modelling shows
poorer f/b performance.
73,
Dave
W0FLS
> ----------
> From:
> harpole@pegasus.cc.ucf.edu%INTERNET[SMTP:harpole#064#pegasus.cc.ucf.ed
> u%INTERNET@email.mot.com]
> Sent: Monday, August 11, 1997 9:45 PM
> Cc: towertalk@contesting.com%INTERNET
> Subject: [TowerTalk] Stack spacing?
>
> Again, what's best stacking distance for three TH-7 s via Dunestar on
> a
> tower either 100 ft or 110 ft or 120 ft ???
> Is additional ten or twenty feet worth it? Especially up to 120 from
> 110ft.' cause that means adding another guy set as per Rohn book ??
> de K4VUD
>
>
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