Hello Marc,
Prop pitch ruined ???? Not so !
There is a brake that originally came with the prop pitch
that many hams did not connect up. Mine handles the wind
with a 35 foot boom plus 13 elements with the brake supplied.
It did move a 80 foot boom into the wind which really didn,t
bother me otherwise I would have increased the brake power
( There is an advantage to having the antenna turn into the wind
rather than it be battered to death )
Usually those that complain of wind rotation have not
connected the supplied brake or given thought to adding one
Of course a small beam (< 20 foot),does not require a brake.
If you use a variac ( or a speed control unit) you can
vary the voltage for any speed desired.( Together with
a controled start and stop if you really want to get fancy).
I do not recomend the use of selsyns, they are a cause of
problems in inclement weather. I made a circular 1 inch
wide band of aluminum with the points of the compass
marked on it and secured it to the mast.
I use a cheap miniature c.c.d. camera ($40 new )aimed permanently
at the band and can see the direction it is pointed at
on a c.c.d monitor or t.v.in the shack.( 40 odd years have
passed since that article was printed )
If the rotor has been modified with securing screws
as shown in the original C.Q. magazine article I
would recommend that you weld 3 -1 inch dia by 1 inch long
to the underside of the bell housing instead so they mesh
with the 3 tapered, weight saving, holes in the circular sun gear.
These are much stronger than the questionable securing method
(shear resistance)originally described and is more inline
with the rotors original design torque abilities.
If the rotor is to be used only for turning an antenna then
there is no need for the oil as there is no danger of overheating
and the non weld additive in the oil does not come into play
As with all rotors use a mast bearing to support your antenna
leaving the rotor to deal only with rotation especially with
a prop pitch where the vertical load bearing system is not
the greatest
Good luck
Art Unwin
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