The true history of the traveling wave tube

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. The young man was Andrei “Andy” Haeff (father of coauthor Andre Haeff), and the device he was working on was an early form of what was later called the traveling-wave tube. This rather exotic type of vacuum tube was a key component in early telecommunications, radar, and television-broadcast systems. In 1952, for example, the British Broadcasting Corp. used the technology to forge a chain of microwave links between Manchester in England and a broadcasting station midway between Glasgow and Edinburgh, allowing the company to distribute television programming to Scotland without stringing lengthy cables. But it was the advent of communications satellites that allowed the low-weight, power-efficient traveling-wave tube to really shine. Nowadays everybody's favorite signals-broadband, phone, TV-can reach almost anywhere on the globe, thanks to satellite- based traveling-wave tubes.