In article ,
the_constructor writes

The bracketry I was thinking of is something like this:

http://www.aerialshack.com/inch-chim...ket-p-346.html

This is the spec of the antenna:

Compact white fibreglass dual-band base antenna for 2m and 70cm.

Frequency Bands 2m/70cm
Max Power 200W
Length 1.7m
Radials 3
Gain (2m) 4.5dB
Gain (70cm) 7.2dB
Weight 0.9kg
Type (2m) 3 x 1/4 wave
Type (70cm) 3 x 5/8 wave

The alli tube that I have is 2" dia and roughly 3/8" wall. As I say, I would
imagine all I need is about 3 feet.

Compared with a moderate TV aerial, that is really quite a light load as
far as windage is concerned. I would be happy to use a single lashing
kit but would use a 9" bracket instead as that will spread the load over
3 bricks. The style of bracket you chose is fine, I have use the same to
good effect.

9" bracket:
http://www.aerialshack.com/inch-chim...et-p-1218.html

I assume it's galvanised, it looks it, find another if it isn't.
--
fred
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