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Andrei Haeff and the Amazing Microwave Amplifier

How history forgot this pioneer of the traveling-wave tube

11 min read
Photo of  Andrei “Andy” Haeff
Photo: The Andrei V. Haeff Papers

photo of Andy HaeffPatent Pending Recognition: The patent Haeff filed in 1933 for a primitive type of traveling-wave tube has been largely ignored.Photo,top: The Andrei V. Haeff Papers; Illustration, bottom: U.S. Patent and Trademark Office

An intense-looking young man stepped out of his engineering lab at Caltech to watch what was happening. In the university’s nearby high-voltage laboratory, gigantic bolts of electricity were leaping eerily from outlandish equipment. It was 1931, and a Hollywood crew was filming the spark-filled special effects for the creation scene in Boris Karloff’s first Frankenstein movie. The serious-minded young engineer loved cinema, but as he walked back to his bench in the Kellogg Radiation Laboratory, he probably had no idea that a new kind of vacuum tube he was working on would in time revolutionize the movie business, enabling TV broadcasters to bounce Frankenstein and countless other films off satellites straight into people’s homes.

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Caltech Team Launches Experimental Space-Based Solar Array

The satellite will test some of the tech needed to wirelessly beam power from orbit

4 min read
A lightweight gold-colored square frame for a solar power array, seen flying in space with Earth in background.

Artist's conception of Caltech's Space Solar Power Demonstrator in Earth orbit.

Caltech

For about as long as engineers have talked about beaming solar power to Earth from space, they’ve had to caution that it was an idea unlikely to become real anytime soon. Elaborate designs for orbiting solar farms have circulated for decades—but since photovoltaic cells were inefficient, any arrays would need to be the size of cities. The plans got no closer to space than the upper shelves of libraries.

That’s beginning to change. Right now, in a sun-synchronous orbit about 525 kilometers overhead, there is a small experimental satellite called the Space Solar Power Demonstrator One (SSPD-1 for short). It was designed and built by a team at the California Institute of Technology, funded by donations from the California real estate developer Donald Bren, and launched on 3 January—among 113 other small payloads—on a SpaceX Falcon 9 rocket.

“To the best of our knowledge, this would be the first demonstration of actual power transfer in space, of wireless power transfer,” says Ali Hajimiri, a professor of electrical engineering at Caltech and a codirector of the program behind SSPD-1, the Space Solar Power Project.

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