Date: Fri, 2 Nov 2012 14:41:07 -0400
From: <w8hw@att.net>
To: <amps@contesting.com>
Cc: w8hw@att.net
Subject: [Amps] NEW Tail Twister Rotator
If interested.
NEW Tail Twister Rotator still in original box. Includes Contains (All new in
box), New control head, New hardware, New connectors, manual New Warranty
Registration card. I purchased one two many units for what I needed.
http://www.ebay.com/itm/330810645370?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649
Contact me direct and ask me me to pay the shipping. w8hw@att.net Save three
ways, $200.00 plus TAX plus SHIPPING on brand new unit. This won?t last long.
Tail Twister Rotator is Hy-Gain big rotator. Turning power 1,000 pounds.
73, Bruce, W8HW
### BTW, the “turning power” is NOT 1000 lbs on that rotor. It’s rated
at 1000 INCH lbs of....”stall torque”. 1000 inch lbs / 12 = 83.33 FOOT lbs
of stall torque. I find it amusing how these rotor makers like to bs the
numbers
on these rinky dink rotors. They will use terms like.. “start up torque.....
running torque...and stall torque” . The start up current on any of those
small motors is typ triple the running current...... hence the “start up
torque” number can be a LOT higher than the
actual running torque. Stall torque is just that, you put enough of a load on
it, that it actually stalls out....as in ZERO rpm for both the motor and
obviously the ant itself.
### In the bigger scheme of things, 83 ft lbs of torque is not much at all.
The flip side is.... IF ant makers torque balanced their ants correctly, you
would require very little TQ to rotate the array. I used K7NV’s software to
design a TQ compensation
plate on a local fellow’s HB 5 el 20m yagi. Without the TQ comp plate
installed, it would literally destroy the tail twister...plus a 2nd tail
twister. He had taken a 204BA......and had added a 5th ele to it....plus
lengthened the boom. He had
mounted the yagi at it’s center of gravity, which then put a lot more boom out
one side vs the other. That alone created the gross TQ imbalance.
## The fix is simple, either mount at the dead center of the boom and use a
counterweight at the light end of the boom. (K7NV’s software will also
calculate the required weight.) Or mount at the CG... and use the TQ comp
plate. You can also use a combo of both schemes. The alternative is to use
a rotor that has WAY more TQ. The tq comp plate scheme was tested by
installing the yagi on a short 30’ tower, with NO rotor..and just let it
windmill. In a 30-40 mph wind it did not windmill...and in fact the owner
could climb up the tower and turn the yagi by hand. It stayed put in whatever
direction it was pointed. The comp plate was then removed, and the yagi will
windmill badly. If stacking yagi’s on one mast, alternate sides on the mast
to account for the
offset between mast and boom.
## IMO, for the $$ they want for the tailtwister, it really is not a big bang
for the buck.... and ditto with the Ham-3-4-5 series with its 800 in lbs of tq.
( 67 ft lbs). Rating any of these rotors in terms of ant sq footage is
ludicrous.
Jim VE7RF
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