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If you haven't read the story of radar development, it's weirdly heroic (wartime or not). It's a very crazy technical story, with weird wartime stuff going on.
If you think Moore's Law was interesting, look at this wikipedia paragraph on the cavity magnetron:
"A cavity magnetron that was introduced by John Randall and Harry Boot at the University of Birmingham, England in 1940 was an improvement over earlier versions.[3]: 24–26 [4] Their first working example produced hundreds of watts at 10 cm wavelength, an unprecedented achievement.[5][6] Within weeks, engineers at GEC had improved this to well over a kilowatt (kW), and within months 25 kW, over 100 kW by 1941 and pushing towards a megawatt by 1943. The high power pulses were generated from a device the size of a small book and transmitted from an antenna only centimeters long, reducing the size of practical radar systems by orders of magnitude, and they could be installed in fighter aircraft.[7] New radars appeared for night-fighters, anti-submarine aircraft and even the smallest escort ships,[7] and from that point on the Allies of World War II held a lead in radar that their counterparts in Germany and Japan were never able to close. By the end of the war, practically every Allied radar was based on the magnetron."
Somewhere is s story of the british folk being asked how a magnetron works, and one of them suggests it works like a whistle. Some smartass asks, "how does a whistle work?" and no one had an answer.
The knowledge of how whistles actually work is recent knowledge. And surprisingly weird.
https://en.wikipedia.org/wiki/Physics_of_whistles
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Even for 10cm (~3000 MHz/3GHz) the high energy pulse that drives them has to be about a microsecond long. Tough to do when all your fastest electronic switches take about 10 uS to switch. So a slow switch dumped a charged up capacitor bank into (initially) a coiled up length of co-axial cable, shorted at one end. The pulse, reflecting off the abrupt impedance change (whatever 50 ohms to 0 ohms), went from long (10's uS) and short (600V) to brief (uS or less) and tall (many KV) and the average energy in the long slow pulse was transformed to the short fast one and dumped into the magnetron, peak power as it says, KW to MW.
Lol then of course radar makes a huge outgoing pulse but then has to switch immediately into a sensitive receiver -- connected to the same antenna -- and switch fast enough to hear the weak pulse reflected back by the metallic target. So this sensitive hand-made diode is subjected to the KW/MW pulse... it's preptected by a clever TR switch tube that arcs internally, protecting the diode.
It's all nuts, and developed by a small handful of very young british engineers. Pretty weird shit. Wartime or not its fkn magic.
One engineer took their one working magnetron model to Bell Labs in NJ, flying on a passenger jety with the thing handcuffed to him and an armed gaurd, for Bell to figure out how to make them reliably/in quantity. MIT et al developed the shit out of them (NJ wasn't being bombed; London was) but it's entirely a british invention.
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