In a message dated 98-05-01 20:37:14 EDT, aljaras@snet.net writes:
<< I have a Rohn HDBX 48'. Presently I have a TH7 at about 3'
above the top of the tower. The tower has a truss bearing on the top
table plate. I would like to put a AW3S 12/17M 3 element cushcraft over
the TH7. The rotor is a HAM IV. Can any one of the antenna and tower
experts give me an idea if this will be too much torque for this type
tower to have to handle with the TH7 and the AW3S on the same mast. >>
The torque of moderate to large systems are guaranteed to cause damage
to BX-type towers. The damage shows up at the top plate and rotator plate.
Because they're just sheet metal, it doesn't take much to get them to crack
and break.
To answer your question, you shouldn't push your luck. I'll bet you a
nickel that you already have cracks in those plates. Adding another antenna
would just aggravate the situation.
If you can come up with a way to reinforce the plates, then you might be
able to get away with it.
Cheers, Steve K7LXC
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