Here is what I have put on Rohn BX-style towers myself:
1-- Hornet/Swann four element trap tribander, I think at least 18 ft.
boom. Installed on HDBX-48 directly out of the Rohn warehouse, by the
book concrete base and all other fittings completely Rohn. 12 ft. mast,
with Hornet one foot above tower, tailtwister inside tower at top, above
Hornet was H-frame of two eleven element 2meter Cushcrafts, and on top was
a G-6 Hustler.
RESULT: It all stayed up perfectly for five years in Carbondale IL. I
once sat in my auto and watched it take tornado-force down bursts, three
in all, while I was reporting to the weather net the cloud rotation
continuously forming over my head! When hit, the whole tower shuddered
for a second and stablized. BTW, I had the beam turned into the oncoming
wind (pointing into the wind). A tornado struck about ten miles away that
day.
2. I now have this same HDBX-48 installed here in FLA again with Rohn
spec. concrete sized base and hardware. I added two more BX-3 straight
sections to the top of this 48 footer, toping it out at 64 feet. Note
this is not a standard BX nor HBX tower because the two BX-3s are bigger
than the BX-2 and BX-1 that comes with the standard BX-64. On this tower
I have a Tailtwister at the 46 foot point (on the standard HDBX rotor
shelf placement), THIRTY feet of mast (.250) going up from that rotor with
16 feet of that mast down inside the tower. Thrust bearing at top. On
the mast from bottom to top are HyGain two element 40 meter beam, three
el. 6meter beam, Cushcraft WARC roto-trap-dipole (3 bander), another
6meter three el beam, and on top a Hustler 2m/440 vertical. This
installation is guyed with plastic rope three ways and at the 64 ft. level
and the 46foot level. And, oh yes, a 160-80-40 parallel dipole hangs from
its 63 ft. level. Tnx to KU4HZ and others for helping put this up.
RESULT: This installation has been up for eight months in winds of 25mph,
gusts to 40 mph. It is still up there.
PS, I would not personally place this latter tower installation within 60
feet of my home, and it is that far away currently.
That's my personal story of my playing with BX-style towers. Read the
Rohn book to understand how the variations of BXs are sold. de K4VUD
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