Friday, 22 July 2011

Errecting antennas in trees

Using a sling shot (Kettie)

I have used a sling shot on many occasions with great success and it works very well. The biggest disadvantage is that one needs to have available (carry) a sling shot and fairly heavy fishing sinker some fairly thin mono filament fishing line and a spooling device.

The weight needs to be fairly heavy so as to ensure an unhindered decent through the branches and leaves. The lead weight (fishing sinker) I use weighs 85 grams. The lead weight and line is shot over the targeted tree limb using the sling shot and the weight is allowed to descend to the ground.

The weight is the removed and the antenna support line is attached to the thin mono filament. The sturdier antenna support line is then pulled over the tree limb ready to attach to the antenna center insulator.

Using the tree arbors underhand toss

The above method is yet untried by me, but certainly has the potential to work very well. The weight used is normally fairly substantial. Geoff ZS6GRL tells me he uses a 400 gram weight made up out of fishing sinkers.

The tree arbors normally use a custom made soft leather bag filled with lead shot, I guess it will minimize the damage if it falls on something it was not meant to fall on?. I notice some radio amateurs use a small plastic water/soda bottle partly filled with water as the weight.

The action of how to launch the weight is best described as follows:
"The secret is to throw underhand, starting off with a gentle to and fro motion and then letting rip."

A most useful link:

The following You Tube video shows the action nicely.

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