Project:Antennas

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A page to collect thoughts about putting up some decent antennas for HF, 2m and 70cm.

Objective

To provide permanent(ish) antennas to enable any licensed member to fire up the shack and reliably get good contacts on HF, 2m and 70cm.

Proposal

For 2m/70cm the club has a collinear which can be mounted atop the trailer, permanently raised to about 15m(?). This aspect will be addressed when the mast is complete.

For HF an antenna needs to be (a) as high as possible, (b) as far from metalwork or conductive structures (like brickwork) as possible, (c) as close to model amateur band dipole as possible or failing that, as long as possible.

It has been proposed to achieve this by running a dipole from above the 'gateward' corner of the shack to the corner of the main building above the back door and to the far side of the main gate.

At the shack and gate it would be supported on the top of a standard 6m aluminium scaffolding pole, possibly augmented by another 2m of aluminium tube or plastic drainpipe (better for insulation) for additional height. Above the back door a simple wall anchor [is there one already?] should suffice.

The wire will necessarily 'droop' to avoid excessive strain on the supports, hence the potential need for extension tubes to clear the height of, say, a double decker bus, or at least a loaded goods truck.


Funding

The project requires:

  • 6m x 50mm aluminium scaffolding tubes - £30ea + £30 delivery (for any number)
  • extension tubes (ali or plastic?)
  • antenna wire (what sort?)
  • steel angle for gatepost (Dean has kindly offered to organize)
  • steel ties (as above)
  • insulators for centre and ends
  • polypropylene rope for ends (JJ is sure he has some and if not the space or tgreer are bound to)

Indicative price at the moment is about £150 and it's been suggested we already have that or most of it in group funds, but failing that we'll have a whip-round and if that fails, start a formal pledge.


Discussion

Please add your thoughts here or edit the text above.