The G6CJ Aerial Circus – A demonstration by Peter G4ENA

Report by Tony G3PJQ

The demonstration and talk by Peter at the March club meeting was very interesting and well delivered. I had not seen the original talk given by G6CJ in the 1940’s to an audience of the IEE and subsequently by others, but it was a novel way of demonstrating the performance of various antenna types.

The demonstration used a microwave source of 3000MHz (3 cm) and model antennas were tested on this scale over a copper ground plane using a sense antenna and oscilloscope. Antennas ranging from a simple quarter wave vertical, through dipoles, yagis, quads and a rhombic were tested and their radiation patterns demonstrated. It was very clear how the spacing of parasitic elements could be introduced and surprisingly even the effect of the ionosphere on fading.

It proves that a practical demonstration is worth its weight in gold compared to sitting through hours of theory. Well done Peter.