I've mentioned this very point here in the (distant) past, when there
were folks anguishing over whether they needed to reduce rotational
torque on their tower. And others worried about shock loads on rotators.
Maybe they do from an engineering standpoint...but noting that there are
many 150'-200' heavily loaded 18" rotating towers still standing after
many years can serve as a sanity check about needing star guys.
That said, tall 18" towers (without star guys) DO twist a lot. If you
stand at the base of one during high winds and look straight up, you'll
see yagis pointed every which way but south, simultaneously. That tends
to be a good thing as far as shock loads on rotators - the tower itself
acts as a shock absorber.
Not good though if you're trying to keep a high gain UHF yagi or dish on
target.
-Steve K8LX
On 1/6/2017 12:32 PM, Jim Thomson wrote:
## heres the part that I dont get. The 6 point guy system will reduce on the
tower
where the..cue rack is installed... almost down to nothing. Is torque even an
issue ?
## these rotating towers all use rings..and the typ 3 guy wires per ring..are
attached to the
ring.... not to the tower. IE: There is nothing to stop the tower from
torquing at all !
The guy wires on the rotating towers just hold up and support the tower, they
dont provide
any torque redux at all. Then folks install 188-220 ft tall rotating tower
assys... with the
usual myriad of large HF yagis on them, typ with a 80m yagi at the very top.
## meanwhile the rotor is at the very bottom, like on the K0XG setups. The
tower appears
to me to be one big.... mother of all torque wrenches. The myriad of yagis are
all bolted to
the same tower face too. How much to these rotating towers actually twist in
high winds ???
## If twist is a non issue on a rotating tower, then why even mess with the
...cue-rack..aka
rohn TA55 assy at all ?? What am I missing here ?
Jim VE7RF
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