20 Nov. 2014 – Terry Giles, G4CDY recreates The Aerial Circus

Terry started with the video of ‘Dud’ Charman, G6CJ made in 1981 by the Bristol TV Group. Dud’s aerials were scaled down versions of those used by amateurs today, and due to the small size of the models the frequency needed was in the microwave band (3200 Mhz). Dud wanted to display a three dimensional impression of the antenna’s radiation pattern that was more meaningful than the usual two dimensional patterns presented in books.

Terry had various aerials and showed their output on a meter projected on a large screen. The outstanding difference between Dud’s equipment and that used by Terry was the 1000v that Dud needed to power the klystron while Terry used a chip powered by the output from his laptop’s USB port!

Then and Now comparisons
Then and Now comparisons.                                                                                             Photo by Paul, G1GSN
The two inch scale
The two inch Yagi                                                                                                    Photo by Paul, G1GSN