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Shaping radio today and tomorrow
Do you remember?
Did you know that the PC turns 21 this year? IBM launched the personal computer, the IBM 5150, in 1981. But even before the PC, IBM introduced a variety of small computers for individual users. The IBM 5100 Portable Computer is one of the PC's ancestors.
Weighing about 50 pounds and slightly larger in size than an IBM typewriter, the 5100 Portable Computer made its debut in the company's General Systems Division (GSD) in September 1975. This portable computer was intended to put computer capabilities at the fingertips of engineers, analysts, statisticians and other problem solvers. Available in 12 models and providing 16K, 32K, 48K or 64K of main storage, the 5100 cost between $8,975 and $19,975. It was available with APL or BASIC programming languages.
Three Problem-Solver Libraries, contained in magnetic tape cartridges, were offered with the IBM 5100 to provide more than 100 interactive routines applicable to mathematical problems, statistical techniques and financial analysis. The cartridge had a 204,000-character capacity on 300 feet of 1/4-inch tape.
Information provided by IBM.
That was then
Intended to solve phase stability and noise problems, the 1982 Phasemaster by Ramko, Rancho Cordova, CA, was a production system that used variable delays in each of the output channels. A sample of the left program channel was encoded on the cue track, and decoding in the playback cycle was compared to its upper track mate. The signal-to-noise ratio for the Phasemaster was 268dB and it offered a 0.25dB frequency response. The distortion level amounted to 0.3 percent max.
The system offered compatability with all present and previously recorded carts. The transition could be made at the users own pace without having to immediately rerecord the station's entire library. The cost of a Phasemaster started at $1,091 and went up to $1,399, depending on the model chosen.
Sample and Hold
A look at the technology shaping radio
Number of radio stations that webcast
A steady decrease since May 2000
Source: BRS Media Inc.
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