The problem with living in Sydney is not just the issue of trying to build or purchase a HF antenna that can be fitted onto the balcony of a one bedroom apartment, but also the problem of an S9 noise floor. So it was that when I was asked to do some dog sitting at my RF quiet North Queensland residence, I packed a HF radio.
Of course, a radio is not much good without an antenna, but in my usual style I decided the best approach was to build one from scratch. I wanted to work only 80m CW and 40m phone and I could have chosen a dipole but the yard is a bit small. I had in the past constructed a 40m/80m trapped sloper referred to as a Lake Eyre Special and I figured this would be the ideal antenna. There are several tall Royal palm trees that would provide the necessary elevation.
I started by purchasing some speaker wire and splitting it into single wires then would 120 turns on to a 40mm pvc form. 10.04 m of wire formed the 40m section which I then tuned using my antenna tuner which I always pack in my holiday baggage :-). I then fitted the coil and double checked the tuning. A slight change to the coil of a few more turns had me back in tune. I then added the top section 1.6m and checked the tuning on 80m. Despite my error of tuning to 3.1MHz instead of 3.6MHz, I finally got things correct. The antenna was hoisted into the tree via the usual sling shot and fishing line method. I always carry my slingshot on holiday for this very purpose.
Now to work some 80m CW in the mornings
73 de VK2KMI es VK4KIM
Shack of VK2KMI 