At 10:19 AM 6/19/96 -0400, K7LXC@aol.com wrote:
> You've got the right idea but the wrong technique. The "trolley" or
>"railroad track" is where you have two ropes or cables and the antenna sits
>on top of them. There's a lot of friction in this type of system as well as
>antennas bouncing around, etc.
>
> I use a tramming system for about 95% of my antenna installs. It'll
>work with guyed towers, trees, etc. In a nutshell, you have a tram wire
>attached to the top of the tower and the antenna is slung UNDER the tram wire
>on an upsidedown pulley. The haul rope goes through a snatch block at the
>bottom of the tower, up through a pulley at the point of tram wire attachment
>and down to the load. When you pull the haul line, the load on the pulley
>goes up the tramline. It takes about 1-2 hours to rig it but only about 10
>minutes to run the antenna up.
A small refinement, with credit to W9LT (or at least he showed it to me).
Rig a short "tiller" of fairly strong aluminum tubing about 3 feet long,
with one end attached to the boom, perpendicular to it and directly under
the tram wire. Attach another pulley to the "tiller", also riding on the
tram line. That way, the beam being raised can't rotate in the horizontal
plane, nor can it rotate around the axis of the boom. Takes all the
excitement out of getting the ends of the elements past the guy wires.
73, Pete Smith N4ZR
n4zr@contesting.com
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