Vic, I've had nothing but bad luck in trying to support long horizontal lengths
of ladder line. In my case, I have two 720 ft bidirectional beverages, which I
initially made of heavy duty commercial ladder line. I supported the line with
wood 4"x4" posts, spaced sixty feet apart, using the little plastic ladder line
clamps, sold in the US by DX Engineering.
After only a month or so, the plastic clamps broke apart because of the
repetitive flexing of the ladder line in breezes. I replaced the clamps with
wood clamps, screwed into the top of the posts. These survived with no problem,
but the ladder didn't. After six months or so, I started having breaks in the
line from the flexing, and after spending two years repeatedly repairing the
line, I gave up and threw away all 1500 feet of the stuff.
Finally, I settled on WD1a military surplus field telephone wire, available
from many sources for about $50 USD in half mile lengths. I use two parallel
lengths of the wire, threaded through twin ceramic insulators screwed into each
4x4 wood support (available from a farm supply store), with a pulley at the far
end to equalize tension in the two lengths. In three years, it has worked
perfectly, with no problems at all.
I'm not disparaging ladder line (or the plastic clamps) at all. The commercial
stuff just isn't designed for long horizontal lengths.
73,
Jim W8ZR
> -----Original Message-----
> From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Vic
> Sent: Saturday, January 06, 2018 01:17 PM
> To: topband@contesting.com
> Subject: Topband: Supporting Ladder line
>
> Has anyone idea's of how to support a long (750 ft) length of home made
> 450 ohm ladder line ?
>
> Is it possible to use it supported from posts in a vertical orientation or
> will that introduce
> imbalance.
>
> I would prefer not to have it supported horizontally due to added cross arms
> being
> required.
>
> Have scoured internet sources but their appears little information available
> on the subject.
>
> I plan to feed a Marconi Tee Vertical (Hairpin Matching) with 9:1
> transformers at each end
> of the ladder line enabling use of 50 ohm coax at each end for convenience.
>
> 73
>
> Vic
>
> G4BYG (G6M)
>
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