Andrew Marino reminisces about the original remote control, the "clicker" of legend, the Zenith Space Command [The Verge]. It was a mechanical marvel, invented by Robert Adler in 1956, and "pioneered a durable, clicky action for controlling gadgets and a simplicity of form that has since been naively abandoned." No batteries required!
The Space Command is a product of mechanical engineering rather than electrical. By pressing a button on the remote, you set off a spring-loaded hammer that strikes a solid aluminum rod in the device, which then rings out at an ultrasonic frequency. Each button has a different length rod, thus a different high-frequency tone, which triggers a circuit connected to a microphone in the television to finish the command.
They couldn't use radio because they hadn't devised a method for pairing devices with specific TV sets. Integrated circuits and microprocessors were more than a decade off: "We can't encode the signal because we can't use 100 vacuum tubes," as Adler put it. The short range of ultrasound removed the need to bother–a problem similarly obviated in later products by using infrared.
That part was logical. I didn't want it to be heard, so it had to be either subsonic or supersonic. Subsonic didn't make sense from a technical standpoint, so there you are. It had to be ultrasound.
Zenith's own "Lazy Bones" remote was the first successful corded example, and its success prefigured the wireless revolution.
Plugged into the TV via its long wire it had two buttons on the top for tuning and volume. At $30 extra (on top of a Zenith TV) this was not a cheap gimmick and at least the name and publicising was quite up front about the way TV remotes would come to dictate our TV habits in the future. The product seemed to sell well at the time, but complaints were made about the annoying trailing wire. By 1955 this problem would become a thing of the past when their new entirely remote TV controllers were released.
I want a phone that looks like the Zenith Space Command. Just a Zenith Space Command but with a full T9 keypad of enormous clunking metal buttons. About the size of a VHS cassette sawn lengthways down the middle, I figure.