Radio Direction Finding

RDF was Radio Direction Finding. It was quite a common technology, so that if you were, say, on a ship or an aircraft, you could tune in on a radio station such as, well, the broadcast stations here in Ottawa, and get the exact direction that station was away from you. It was a smoke screen, as I say, and RDF, for a good part of the time that we were in the service, was the name given to this equipment. But radar, the Americans coming along with ... it became what they called the arsenal of democracy. They produced huge amounts of radar equipment. They introduced the high tech people from Bell Labs, Lincoln Labs in the States, and the various military schools, and towards the end of the war, really dominated the technology. They had the capability, the assets, so that’s why radar. And nowadays, whether it’s a speed gun on the highway or something that directs you when you’re coming into an airport, that’s radar. And it all goes way back to the very early ... what would, I guess you’d call it, the secret weapon work that Watson Watt was doing in 1935 in Britain when he discovered that you could detect aircraft by bouncing radio waves off them. That was in 1935. Fortunately, the British government caught onto the value of this and built radar stations as a chain around Britain to warn, give advance warning of, say, enemy aircraft coming from the continent. But radar, it’s it now … no longer RDF.