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Re: [TowerTalk] My New 40M Antenna

To: Pete Smith <n4zr@contesting.com>
Subject: Re: [TowerTalk] My New 40M Antenna
From: "Jim White, K4OJ" <k4oj@tampabay.rr.com>
Reply-to: k4oj@tampabay.rr.com
Date: Thu, 18 Dec 2003 17:42:25 -0500
List-post: <mailto:towertalk@contesting.com>
The tram is a wonderful thing.....

A "tiller" really helps on bigger beam but smaller tribanders may not need it as much...

By pulling the beam up along the tram line with the "tiller" the line the tiller seeks is "pointed" at the pulley at the top of the tower that the pulling rope passes through...

By making the tiller lie in a plane that is slightly different (leading end lower than that spot would be on an element) than the elements the antenna will ride up the tram with the high end element tips higher with respect to the tram line.

If your top guy wires are close to the top of the tower, the sag of the elements may cause them to come close to the guys - the slightly different plane of the tiller will elevate the leading tips as the tiller seeks the line pointing at the pulley... this can help avoid the element's tip versus top guy snag scenario from occurring.

Once the beam gets to the top of the tram it is a dead lift on the gin pole and the tram lines no longer are used so there is no problem with the antenna being "flat" at that point!

I noticed from the great pix KB9CRY posted he used some weights to balance the beam while tramming it up... I have found a small hand sledge works great for this - you can put a wrap of duct tape or a big hose clamp and fine tune the balance while tramming - NOTE - if you use some sort of counterweight it is better to have a heavier one closer to the mast than one which is lighter but farther away if that distance means you cannot reach it from the top of the tower!

I have also used the hand sledge to "balance" a mast so that the shorter side from the middle/lift point is "down" during a lift. You can buy some ability to get the mast up higher by making the "bottom" side heavier... aids in minimizing pucker factor!

Seasons

Jim, K4OJ




Pete Smith wrote:


At 02:30 PM 12/18/03 -0600, Chuck Sudds wrote:

Thanks for the photos and information about the installation, Phil! Very impressive. Looks like you had fewer problems then I did getting my 5el 20M monobander atop my 90ft Rohn 45G. Bent a Rohn gin pole in the process. Next time, the "Tram System" will definitely be used!


Many people argue for the use of a backstay because, as Phil says, this puts a lot of stress on the mast. W9LT (now WA7LT) taught me how to do this using a single cable and what he called a tiller, which is a short piece of tubing u-bolted to the boom like another element. Put a pulley on the end of the "tiller," also running on the tram line, and you can adjust how high the leading ends of the elements ride so they don't hang up in the top guys as you approach the tower.


73, Pete N4ZR Happy Holidays Check out the World HF Contest Station Database at www.pvrc.org/wcsd/wcsdsearch.htm



_______________________________________________

See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.

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_______________________________________________

See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.

_______________________________________________
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http://lists.contesting.com/mailman/listinfo/towertalk

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