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RE: Design of microwave towers

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Microwaves are sensitive to rotation. I have had success in requesting the 
microwave engineer to specify a maximum rotation allowed. I considered 
that this is for a 2 year wind or earthquake return period. Recall the AISC
preliminary report recommending 0.75 load factor for temporary structures.
Of course one would design the tower for the full code requirement
the antenas acting as sails) rotation is important.

I have also had troubles mounting antenas on the wood framing of
whose designs are non-compliant for new structures. Clever positioning 
over columns and spanning supports over joist togirders. Very bouncy but 
little rotation. 

The antena industry is full of self made cowpersons who will do anything to
do what the engineer wants. Just wait when you tell them the antena tower
to be over a column, it restricts the access to below for equipment.
I would get the response "nice design, how ever we have already installed 
it based on your proposed idea for a design. My bill would triple to design
But the industry always paid (after miles of billing paper work)

I recall a request for proposals in SF to mount many antenas on many
buildings. I laughed to myself and never made a proposal. They will find
who will forget the cowperson factor. and the old building factor. and hey,
how about the newcode factor and then the ASD unfactoring factors. 
So I factored myself out.