No Batteries.

Here's something interesting... if you're a bit geeky. We are ALL a bit geeky. Like the Russian said to Rambo before he turned on the juice: (Okay first he said "You may scream," but that's not the part I mean. The second thing he said was-) "There is- no shame."

2. ZENITH SPACE COMMAND TV REMOTE CONTROL, 1956
Remember having to get up off the couch to change the channel on the TV by hand? Of course you don't, thanks to Robert Adler's stunning breakthrough, the wireless remote control. Zenith had been meddling with remotes since 1950; its Lazy Bones remote (no, seriously, that's what it was called) simply ran to the TV with a wire. The first wireless remote came in 1955: The Flash-matic was basically a flashlight you shined at one of the TV's four corners, depending on whether you wanted to change the channel up or down. The problem: On sunny days, the TV would change channels by itself. In 1956, Adler had a better idea: Use ultrasonic sound to control the TV. His Space Command remote had four buttons that, when pressed, struck an aluminum rod located inside the unit. A receiver in the TV detected the sound, and depending on the pitch, changed channels or muted the volume. No batteries required. Various forms of ultrasonic technology were the standard all the way until the 1980s, when infrared took over.

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