100 years 100 innovations


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15.  Regency TR-1

Right before Christmas in 1954, Regency (a division of Industrial Development Engineer Associates of Indianapolis) introduced the TR-1, the first commercially available transistor radio.  The design was a four-transistor (parts by Texas Instruments), super-heterodyne configuration.  About 100,000 units sold in 14 months of production.  Interestingly, if you convert the 1954 price ($49.95) to today's dollars, you come up with a figure that is near to what an Ipod costs now.


Courtesy of Airborne Audio, Lenexa, KS

14.  RCA 44

The ribbon-type microphone (also known as the velocity type) was the last of the four basic microphone types to be developed (the other three being carbon, dynamic and condenser).  RCA introduced the 44A in 1931, and it was an immediate hit because of its smooth tone and its well-defined directionality.  The 44B and 44BX followed in 1936 and 1938 respectively.  They became fixtures in everything from movie sets to radio studios.
The low-frequency response of ribbon microphones makes them popular among voice talent. As we all know, jocks like that larger-than-life sound, and it's always an advantage to get it from the mic itself without having to make it up with outboard equipment.


13.  Regenerative feedback

Among the early developments in the art of receiver design was regeneration, a design technique in which a particular tuned amplifier is operated with a high amount of positive feedback, thus increasing its gain.  Major Armstrong patented this concept in 1914, but Lee de Forest patented it as well in 1916.  Thus a contentious, 12-year patent suit began, eventually winding up in the Supreme Court, which ruled in favor of de Forest.  Armstrong showed them though; he patented super-regeneration in 1922 and FM later on.


12.  Computer Microprocessor

Intel introduced the first microprocessor in 1971. It was invented by Intel Engineers Federico Faggin, Ted Hoff and Stan Mazor.  The design was precipitated by a special product order from a Japanese company called Busicom.
Later, Busicom went out of business but Intel had purchased back their design and marketing rights.  Thus was born the original: the 4004.  At 1/8" by 1/16", and holding about 2300 MOS transistors, it actually had as much computing power as the 1946 ENIAC.  Interestingly, the Pioneer 10 spacecraft, launched in 1972, made use of the 4004.
Their functionality has made microprocessors ubiquitous. Still, sometimes I wonder if even the most simple of devices, like a toaster for example, really need a microprocessor.


11.  CBS Labs Audimax/Volumax

While it seems that audio processing has been around as long as broadcasting itself, this is not the case.  Until the late 1950s “riding gain” on a program was often done manually.  This changed when CBS Labs introduced the Audimax in 1959.  It was a simple wideband AGC.  As FM radio started to come in to its own in the late 1960s, CBS Labs introduced the Volumax, which was an HF limiter.  The Audimax and Volumax then worked together as a pair.  Some of the last units produced were the 1RU Audimax 4450 and the Volumax 4111.  The modern era of audio processing for broadcast had begun.
By the late 1970s, the Max brothers had been displaced by the newest FM audio processor, so many broadcasters today have never used them.  Interestingly the processing pair still finds use as special effects processors in recording studios around the country.




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