At 11:40 PM 8/26/02 -0500, Joe wrote:
>Tower Building 201
>
>Need help with putting up a new tower. This is my second tower, the first
>was on a hinge.
>
>I have 5 sections of Rohn25G and one top section. I intend to use one of
>the sections as a base. For now I would like to place a Diamond HF
>vertical (mounted on the side) and a Cushcraft 144/440 on top w/a rotor.
Do you really mean "HF?" I think it will prove unsatisfactory, being that
close to a grounded tower.
>My house has a 13' foot peak and a 3' overhang. I think it would be best
>to mount the bracket to the wall. I am told by Rohn to not go over 30'
>above the bracket.
When you say you were "told", do you mean that you got this information
from the Rohn catalogue? If you don't have one you need one, because
that's the source of all the engineering drawings you'll need.
The problem with house brackets is that they transfer a lot of load to the
structure. For what you now plan, something minimal might be fine; if you
were to add an antenna with significant wind area later, you could do
serious structural damage to the house unless you beef up the support
behind the bracketing. There was an article in QST a few years back that
covered this territory.
>I am also told by Rohn to dig down 4' with 6" of gravel for the base.
>
>My goal is to have a decent tower that I can use for quite awhile and grow
>with. My objective is to build it this fall AND TO DO IT RIGHT. That is
>where you guys come in. Do you have any suggestions to help me meet my goal?
Questions this broad are hard to answer helpfully. I think you'd be well
advised to start by reviewing the Rohn catalogue and then look at the
archives of towertalk. Go to www.contesting.com and look in the left
margin for a box marked "list search." Then enter a series of keywords
including towertalk. A sample entry might be towertalk guy anchor. The
search engine will return ALL messages on towertalk since its inception
that contain the words guy and anchor. Not very laborious. You'll quickly
come to recognize the knowledgeable writers on the reflector. Then you can
come back with specifically targeted questions on the things you remain in
doubt about.
73, Pete N4ZR
Sometimes a tower is just a tower
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