[UK-CONTEST] ANTENNA SUPPORT

[Mark Marsden]

Hi Don

Depending on the stub mast, if it is a fibre glass Spiderbeam pole e.g., a 6" long rod of PTFE in the top drilled to take the dipole support, will not bind. A KISS approach is best here.

73 Mark G4AXX

-----Original Message-----
From: uk-contest-bounces at contesting.com [mailto:uk-contest-bounces at contesting.com] On Behalf Of Don Beattie
Sent: 24 June 2009 11:01
To: Uk-Contest at Contesting.Com
Subject: [UK-CONTEST] ANTENNA SUPPORT

Slightly OT, but I guess there's someone here who knows the answer.

I am planning to try putting the centre of a wire dipole significantly above the rotator/beam on a tower. I plan to fit a fairly long stub mast above the beam, and to attach the centre of a wire dipole to the top of it. The wire should clear the beam's elements whatever direction it is pointing as the ends of the dipole are quite high. This should put the centre of the dipole at about 90ft.

What's the best way of attaching the dipole to the top of the stub mast, so that the beam can still be turned without it winding-in the halyard ? Do I need to find a proper slip bearing, or is there a sneaky and cheaper way ? Or do I just leave 30 cm of slack halyard between the pulley and the dipole centre insulator, and let the thing wind/unwind as the beam turns ?

Thanks

73

Don, G3BJ


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