Wednesday, May 13, 2015

80m antenna, take 3

It's tough putting up a decent antenna for 80m. The sheer length involved excludes many amateurs without large blocks of land. My shack is at the back corner of the block and I've had several shots at this.

Mostly I've used an inverted V dipole hung from a large tree at the back of the block, actually in the neighbour's yard, but the legs of the dipole have to make right angle turns and run along the fences. Recently I tried a full length dipole along one side fence line - it transmitted quite well but was very poor at reception.

This week I tried an inverted L. A quarter wave length up as far as I can go in the tree and then pulled sideways and a bit down to a pole on the side fence. Early tests with Mal, VK2BMS, indicate that he's the strongest I've received him and I'm the strongest he's heard me.

An earth stake kindly donated by Robert, VK2ZNZ, provides an excellent earth (particularly with all the recent rain) and the antenna tunes up beautifully.

It may well be that it's all ground wave between our houses, although Mal is running a dipole, but we'll see in the weeks ahead how it goes.

Naturally, I'm thinking of how I can combine my interest in drones with ham radio antennas.

Flying a micro-drone with a video camera attached, here's a closer view of the tree.


Using micro-drones to inspect antennas is actually useful. Here we see the support of the top of the 80m inverted L. Just below you can see my 40m dipole's balun.


When there's not too much wind I can take the drone up quite high.



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