> If you can find a copy of Dave Leeson's "Physical Design of Yagi
Antennas"
(out of print) he explains how to calculate all the moments created by your
combination of wind speed, boom/mast lengths and material types. Then you
select the proper material, length and wall thickness to withstand those
forces.
We used Dave's book as a guide for our MARC Program (Mast, Antenna
and Rotator Calculator). It's ten bucks at championradio.com.
> That stack sounds like a big load on the base of the 2" mast, but
whether it will hold depends on the yield strength of the chrome moly mast
you use.
IMO most of the people that buy expensive chromoly masts waste
their money when there are other cheaper alternatives available; e.g. SAE
1026, DOM 520. There is a whole chapter on masts in my UP THE TOWER book.
But in this scenario the mast is beside the point. I'd say the
tower won't take the local windspeed conditions with the array that's being
proposed.
Cheers,
Steve K7LXC
TOWER TECH
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