Monday, January 29, 2007

The Remote Control

Remember when you actually had to go to the television and turn it on and off? Well, some of the baby boomers remember.

Then along came the remote in 1956. Remote control technology was developed for military use (the Germans used remote control motorboats during W.W.I.) and in the late 1940's the first non-military uses for remote controls appeared (i.e. automatic garage door openers.)

Zenith Radio Corporation, the company behind the development of the remote control, created the very first television remote control in 1950, called "Lazy Bone." Lazy Bone could turn a television on and off and change channels, however, it was not a wireless remote control. The Lazy Bone remote control was attached to the television by a bulky cable, which the consumer did not like (the cable caused tripping).

Zenith engineer, Eugene Polley created the "Flash-matic," the first wireless TV remote invented in 1955. The Flash-matic operated by means of four photocells, one in each corner of the TV screen. The viewer used a directional flashlight to activate the four control functions, which turned the picture and sound on and off and turned the channel tuner dial clockwise and counter-clockwise. However, the Flash-matic had problems working well on sunny days, when the sunlight could change channels randomly.
The improved "Zenith Space Command," remote control went into commercial production in 1956. Zenith engineer, Dr. Robert Adler who based his invention on ultrasonics, designed the Space Command. Ultrasonic remote controls remained the dominant design for the next twenty-five years, and as the name suggests they worked using ultrasound waves. The Space Command transmitter used no batteries; inside the transmitter were four lightweight aluminum rods that emitted high-frequency sounds when struck at one end. Each rod was a different length to create a different sound that controlled a receiver unit built into the television.

In 1956 Robert Adler developed "Zenith Space Command", a wireless remote. It was mechanical and used ultrasound to change the channel and volume. When the user pushed a button on the remote control it clicked and struck a bar, hence the term "clicker". Each bar emitted a different frequency and circuits in the television detected this noise. The invention of the transistor made possible cheaper electronic remotes that contained a piezoelectric crystal that was fed by an oscillating electric current at a frequency near or above the upper threshold of human hearing, though still audible to dogs. The receiver contained a microphone attached to a circuit that was tuned to the same frequency. Some problems with this method were that the receiver could be triggered accidentally by naturally occurring noises, and some people, especially young women, could hear the piercing ultrasonic signals. There was even a noted incident in which a toy xylophone changed the channels on these types of TVs since some of the overtones from the xylophone matched the remote's ultrasonic frequency.

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