Since you don't climb, Forget the pulley all together. It is not a matter
of IF but WHEN the pulley will rust or fail . A marine pulley may last 8 -
10 years but it will eventually rust and fail
Just have the utility guys attach a few feet of 3/16 or larger EHS guy wire
thru one end of a large johnny ball insulator around the tree trunk itself
or a large branch at the top. Make it a large loop so the trunk or branch
can continue to grow. Fasten the EHS loop together with a couple of 3/16
inch cable clamps and forget about it.
I think my L is about 150 feet of # 10 stranded insulated electrical wire.
90 feet vertical and 60 feet horizontal. I put a thimble on one end of the
wire fastened with two cable clamps. I tied about 100 feet of black
dacron rope to the thimble. The other end of the rope is fastened to a tree
in the front yard .
Once the utility guys get the johnny ball mounted, have them feed the wire
down thru the johnny ball and down to the ground at your coil or matching
device. Mine runs down to the ground where it attaches to a vacuum
variable capacitor (mounted in a plastic box I got from K-mart) to shorten
the antenna for best VSWR.
The wire slides very easily thru the end of the johnny ball insulator and
I can raise and lower the L at will and never worry about a pulley
malfunctioning or rusting. i got my rope from the wireman. Just get the
best quality and largest size rope you can afford that fits easily thru the
johnny ball.
I use a second johnny ball attached with a couple of feet of EHS guy wire
at the top of the tower with a continuous loop through the other end of the
johnny ball as a haul line from the top of the tower to the ground. It
also works nicely for pulling up a sloper or inverted vee when needed. In
20 years at this qth I have gone thru 3 marine pulleys. They always seem to
fail at the time they are needed most.
No failures since I used the johnny ball insulator method. You will likely
see some wear on the rope after 4 or 5 years. If you do see some wear,
just disconnect the inverted L from the matching device, Tie a rope on the
feed end of the wire, pull it up the tree until the thimble comes within
reach at the far end , cut the old rope, tie on another length of rope and
pull new run up and thru the johnny ball, reattach the antenna to the feed
point and you are good for another 5 years or so.
press on regardless
73
Chet N6ZO
----- Original Message -----
From: "Peter Dougherty" <w2irt@comcast.net>
To: "Nick Pair" <daweezil2003@yahoo.com>; <towertalk@contesting.com>
Sent: August 24, 2006 6:22 PM
Subject: Re: [TowerTalk] Inverted L questions
> At 05:57 PM 08/24/2006, Nick Pair wrote:
>>I have one suggestion. Use a continuous loop of UV resistant rope
>>through the pulley. With a pulley at ground level you can use the
>>loop splice point to attach your L or whatever you choose, This way
>>if wire breaks you will have a haul down rope all ready to pull the
>>antenna attachment point back down. Also you can put whatever you
>>choose at ground to take up the tree sway and keep tension on the loop.
>>You didn't mention where the end of the horizontal wire is anchored.
>>This also needs sway protection and might end up a similar
>>arrangement as the main support.
>
> Looks like the loop idea is the winner. As I mentioned off-list to
> another kind soul who replied, I'm an ex-apartment dweller (small
> city apartments all my adult life) and thus never needed to know
> about such things. I'm trying to visualize how to do this. Any online
> drawings/photos, etc?
>
> Also, wouldn't a loop of rope get caught up in all the branches
> sticking out of the tree, making it very difficult to raise or lower
> the insulator and the wire it supports?
>
> As for the far end of the horizontal wire, after the end insulator it
> will connect to 3/16" dacron rope, over a marine pulley in a distant
> tree, and to a weight of some sort (yet to be figured out) to keep
> the whole shee-bang taught.
>
>
>
> Cheers,
>
> Peter,
> W2IRT
>
>
> _______________________________________________
>
>
>
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