In a message dated 98-10-04 00:32:14 EDT, kc5ajx@hotmail.com writes:
> I noticed something strange while studying the Rohn book the other
> night. I was looking at the difference between Rohn 25 @ 70ft and 100
> ft, I mistakenly open to the Rohn 45 section instead of the Rohn 25
> section I noted the the allowable area for round and flat member is
> higher for Rohn 25 than for Rohn 45 at the same height is this a
> misprint? My book is dated Dec 1997
Read "General Note #4" for the 45G. You'll see that they have taken 8
sq.ft. away from the tower loading spec to allow for a commercial symmetrical
antenna mount. Add the 8 sq.ft. back into the figure in the drawing and
that'll make it apples-to- apples. The 25G does not have this 'net/gross'
situation.
> Another thing with the current thread on rebar cages I noticed that the
> Rohn book doesn't call for one. I can only assume that the rebar cages
> are for crankups or another brand of tower or is this another issue I
> have to consider? I wasn't planning to use one in my plans.
Rohn calls for rebar of a certain size in a specific configuration. The
Rohn base and anchors are MUCH smaller than a self-supporting tower base and
do not need as much reinforcing.
Cheers, Steve K7LXC
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