[TowerTalk] rs-232 rotator for a C36XR

[Pete Smith]

I was struck by K7NV's comments on what's really necessary to rate a
rotator, as recalled and reprinted by KS4XG.  We have Force 12 quoting wind
area, worst-case wind torque at rated speed, and weight.  We have Yaesu
quoting weight, wind area and K-factor (which is a worst-case polar moment
of inertia, if I understand it correctly... or as Kurt suggests, really
experientially based, and not physics at all).

But what we don't have are numbers for matching the C-36XR to a rotator,
other than the K-factor.  Presumably, Yaesu's "torque capacity" is
something like Kurt's "stall torque" figure.  Stall torque for a T2X is
given as 1000 inch-pounds; the G-1000 has a rated torque capacity of
somewhere between 520 and 954 inch-pounds.  

Clearly, the braking capacity of the G-1000 (5208 inch-pounds) is plenty to
hold the C-36 at rated wind load (<120 inch-pounds of wind torque), so the
only remaining consideration is -- can it be started turning by 520
inch-pounds of torque.

I have always understood that Force 12 used Yagistress to design its
antennas.  If that's the case, then presumably Force 12 can tell us what
starting torque is required for their antennas in a worst-case situation
(maximum wind torque plus polar moment of inertia).  

Am I understanding this correctly?  Do we need another standard antenna
specification?

73, Pete Smith N4ZR
n4zr@contesting.com 

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