Jim,
I have the same installation using a CT-100. I use schedule 40 PVC pipe
3/4" as stand-off. I drill out foles forthe u-clamp's threaded ends to pass
through the PVC. You can adjust the lengths of the PVC pipe so that the feed
line remains relatively straight as it comes down the different tower
sections. I' using 450 ohm ribbon cable. I attach the ribbon to 3/4" end
caps which fit over the ends of the PVC pipes using nylon screws. I suspect
there are lots of different methods to attach the ribbon cable and they
probably all work pretty well.
Good luck,
dave
wa3gin
----- Original Message -----
From: "Jim McDonald" <jim@n7us.net>
To: <towertalk@contesting.com>
Sent: Sunday, April 01, 2007 11:41 AM
Subject: [TowerTalk] Window ladder line & crank-up tower
>I hung an 80M inverted vee fed with window-line balanced feeders hung off a
> cross-arm at the top of my 89' crank-up tower. I don't have the feedline
> attached to the top of any sections (yet?) and have the bottom of the
> feedline temporally attached at the bottom of the tower. I do have the
> feedline twisted to minimize wind loading, but it still acts like a sail
> in
> high winds.
>
> Before I lowered the tower partially, I had visions of being being lifted
> off the ground when I was holding the bottom of the line. Well, it was an
> uplifting experience.
>
> Is there a satisfactory solution to using window line with a crank-up
> tower
> of this height? If I use wood or other non-conductive standoffs, assuming
> I
> can figure out how to attach them to the tower, I fear the feedline will
> wrap around the tower or get caught in it if it's partially or fully
> retracted.
>
> Would true open line be better?
>
> I think not being able to attach it to a fixed tower makes balanced
> feeders
> a deal killer with any significant wind.
>
> I know, shunt feed the tower, though the tower isn't always fully extended
> (it's only permitted to 75').
>
> Ideas appreciated.
>
>
> Jim N7US
>
>
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