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Rotor leads

To: <towertalk@contesting.com>
Subject: Rotor leads
From: w5hvv@aeneas.net (Rod Fitz-Randolph)
Date: Tue, 10 Dec 1996 07:47:01 -0600
"C. R. Crutchfield, K5BC" <crc@phoenix.net> wrote:

>I have a tower located 200' from the radio shack, the tower is 125'
>tall.  My plans are to run the leads in conduit below ground and am
>wondering how well the rotor (TailTwister) will perform.  By the time I
>get through running the lead for the rotor it will be approx. 350'.
>The lead I have is 2/12 gage and 6/14 gage.  I'm hoping the voltage drop
>won't be that much but am not sure.  Any suggestions?
>
Bob, I have a similar situation: my tower is 250 feet from the shack.
I rented a ditch witch and dug a trench 4" wide and 18" deep from the
wall back of the hamshack to the base of the tower.  I then installed
 3" PVC sections for the full length, bringing it up to a 3"-2" reducer
at the hamshack wall, making sure that the joints were well sealed.  At
the 2" end of the 3-2" reducer, I installed 2" UV protected PVC and
brought it through a hole cut in the wall for that purpose.  at the far
end of the 3" PVC pipe (at the tower) I again used a 3" to 2" reducer
and bought 2" UV protected PVC up to a NEMA box mounted about 5 feet up
on the Rohn 25G.  I placed a piece of foam rubber cut with scissors to
approximate a ball that was slightly larger than 3" (only barely larger)
and ran a large needle through the middle of the ball with stout nylon
twine attached and knoted it around the ball.  I then inserted the ball
in the 3" PVC (before I had attached the 2" reducer to it!!!) and blew
it through the 250 feet of 3" PVC in about 10 seconds with a gas powered
leaf blower.  Worked like a charm.  Then I attached a 1/4 inch nylon
rope to the twine and pulled it through.  The 1/4" nylon rope was
sufficiently strong enough to pull 7/8" Hardline AND 4 each 250' lengths
of Romax (sp?) that consisted of 2 strands of 12 ga copper and a ground
strand of 14 ga. copper each.  Those 12 wires supplied 6 strands for the
tailtwister and 5 for the T.I.C. Rotor Ring.  Only 6 wires are required
for any of the HAM-2, -3, -4, or TT2 type rotors (remove the motor
starting capacitor from the control box and place it in the NEMA box on
the tower ... or even up under the rotor if you can waterproof it).
Then you won't need but six wires for the HAM-M/TT2 style rotors.  The
tower is 130 feet tall so the total run from the shack to the Tail-
Twister is almost 400 feet.  I ran the regular commercial heavy duty
control cable up from the NEMA box to the tailtwister and Rotor Ring.

The 7/8" hardline was connected to an Ameritron RCS-4 Relay Box that
was already installed in the NEMA box to weatherproof it (regardless
of what Ameritron says, they WILL rust if in a corrosive environment -
placement of the RCS-4 in the NEMA box precludes that.

Hope this helps.  The shame of it all is that, after putting up a
first class installation with the 402CD at 140' and the TH7DXX at 132'
and a Classic 33 at 68 feet, I have to sell the house and leave this
next spring!!  Know of anyone that wants an English Tudor Style home
on 4.3 acres in the middle of Jackson, TN?.....complete with a decent
antenna site?


Roderick M. Fitz-Randolph
w5hvv@aeneas.net
79 Highland Hills Cove,
Jackson, TN  38305
(901) 661-9278 (Phone - after 10 AM and prior to 9 PM)
(901) 664-7539 (FAX - any time of day or night)



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