Vale: Graeme Cohen – Inventor, Engineer.
Many thanks to David Murphy, Adelaide Chair, for this sad news. Below is the notice he issued.
Members will be saddened to learn that Graeme recently passed away. We offer our condolences to his family and friends. His funeral will be at 11:00 am, Tuesday 4th August, 2015 White Lady Chapel, 491 North East Rd, Hillcrest SA 5086
Graeme had a long and varied career, from running his own transceiver company in Sydney, working at Philips Micro-electronics at Hendon in the 1980s, Adelaide, joining and leaving CODAN Adelaide more than once, and consulting with Duntech about audio power amplifiers. His major activity was with DSTO and related entities, working on the Over the Horizon radar and its successors. A recent project was a compact and powerful HF radio transmitter module, using balanced circuitry and ingenious coupling transformers of his design.
He was a prolific inventor, and had the craft and engineering skills to make many of them himself.
He was an analogue man, inventing the double balanced microphone preamplifier while at Philips, and a plethora of vacuum tube based audio amplifiers. His 1984 balanced microphone design lives on in modern IC designs, the SSM 2015, and the THAT Corporation 1510 and 1512. He was always thinking in terms of balanced bridges, symmetry, circuits which cancelled distortion, had improved common mode rejection ratio, and so on. He was proud that he had presented papers at all the AES Australian Regional Conventions in the late 80’s and early 90s.
Apart from RF work, some of his other hobbies were audio, photography, steam engines, red wine, and animated discussion about anything related to audio!
An AES member has hosted the following pages:-
LeonAudio.com.au/cohen a few pages about Graeme Cohen
LeonAudio.com.au/AES an unofficial and informal collection of notes from local meetings
2 August 2015 David Murphy, Chair, Adelaide Section, Audio Engineering Society