Chapter 01
An idea that came out of the aviation world
In the early 1980s John Franks was a young electronics engineer at Marconi Avionics, designing equipment for aircraft. It is a discipline with a particular kind of pressure: nothing is allowed to be approximately right, and nobody is impressed by an elegant solution that fails once. His speciality was ultra-high-frequency power supplies - the unglamorous end of electronics, and the end where most of the real problems live.
While he was there he worked out something that had nothing to do with aeroplanes. By coupling an amplifier's power supply rails through strong magnetic flux inside a specialised high-frequency transformer, he could remove the short-term distortions that appear when large currents feed back into the ground loop. He called it Dynamic Coupling. It worked, and it was judged far too expensive to put into a product.