Here's a copy of a post I wrote 2 days ago on this very topic
and some comments on the TR44 and wide spaced 3L20.
Tom N4KG
I have used a TR44 rotor in the past on a 2L Quad, TH7, and
stacked 5L10 / 4L15. While the rotor will turn those antennas,
it WILL NOT HOLD them in even a modest wind.
A 32 ft boom seems awfully wide for a 3L20, being .45 WL long.
This can produce decent gain, but very LOW F/B. That boom
length would be more suitable for a 4L design. A very good
3L20 can be realized on a .35 WL boom (24 ft) with over 8 dBi
gain and moderate F/B. Gain rises very slowly with boom length
between .35 and .70 WL so the return vs investment in material
and compatible rotor and tower is minimal in this range.
Tom N4KG
On Tue, 6 Nov 2001 "Steve/n0tu" <n0tu@webaccess.net> writes:
>
> I have a run of almost 300' to the tower, and I thinking of mounting
> the rotor starting cap in a junction box at the base. Thoughts?
>
> Steve/n0tu
>
For my distant towers, I run regular 8 conductor rotor cable from
the rotor to the base of the tower. I connect the start cap at the
base of the tower and insert it in a small (prescription) plastic bottle
with the open end down. I run 3 conductor #14 house wiring to the
house, one for each side of the motor and the brake. I connect
the ground to the shield of the CATV Hardline. For the position
indicator pot, I run a pair of small conductor wires (#20?). This
works fine on a 600 ft run (95 ft tower 400+ ft from the house)
Tom N4KG
On Sat, 10 Nov 2001 W0AH@aol.com writes:
>
> This week I put a 3 el wide spaced (32' boom) 20M beam on top of my
> 94' Rohn
> 25, 160M, shunt fed vertical. It's fixed at Europe, but I would
> love to
> rotate it using and old CDR TR4 rotator. The tower is about 300'
> from my
> shack, so I would need almost 400' of 8 conductor cable. Belden
> makes a
> light duty rotor cable, product 8448- 2 x 18 guage and 6 x 22 guage
> and a
> heavier duty rotor cable, product 9405 - 2 x 16 guage and 6 x 18
> guage.
> General Cable's heavier duty rotor cable, product C4090 product, is
> 2 x 16
> guage and only 6 x 20 guage.
> Radio Works has a rotor cable that appears similar to Belden 9405.
> Does any
> one know if any of the above are husky enough for a 400' run to a
> CDR rotator?
> The Belden 9405 costs about $320 for 500 feet. Not sure of the
> General Cable
> price, but the Radio Works cable costs about $175 for 500 feet.
> These costs
> are more than I have in my Piggy bank! Are there any less expensive
> options?
> In the mean time, my antenna remains fixed on Europe and is about 6
> db
> better than my KT34XA at 41'.
> Doug W0AH Woodland Park CO
>
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