Such sad news and my thoughts go out to Bob's family. I routinely saw Bob by the fence at Bankstown doing just as I was, admiring whirly birds! My scanner even runs an aerial given to me by Bob because the default one my original AOR device came with was pretty ordinary!
Bob's "On The Airbands" column in Australian Aviation was always one of my first reads whenever a new mag came my way.
For those who are unfamiliar with On The Airbands, here's a sample from July 2001.
