Do you remember?
Didyou know that the PC turns 21 this year? IBM launched the personalcomputer, the IBM 5150, in 1981. But even before the PC, IBM introduceda variety of small computers for individual users. The IBM 5100Portable Computer is one of the PC's ancestors.
Weighing about 50 pounds and slightly larger in size than an IBMtypewriter, the 5100 Portable Computer made its debut in the company'sGeneral Systems Division (GSD) in September 1975. This portablecomputer was intended to put computer capabilities at the fingertips ofengineers, analysts, statisticians and other problem solvers. Availablein 12 models and providing 16K, 32K, 48K or 64K of main storage, the5100 cost between $8,975 and $19,975. It was available with APL orBASIC programming languages.
Three Problem-Solver Libraries, contained in magnetic tapecartridges, were offered with the IBM 5100 to provide more than 100interactive routines applicable to mathematical problems, statisticaltechniques and financial analysis. The cartridge had a204,000-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 1982Phasemaster by Ramko, Rancho Cordova, CA, was a production system thatused variable delays in each of the output channels. A sample of theleft program channel was encoded on the cue track, and decoding in theplayback cycle was compared to its upper track mate. Thesignal-to-noise ratio for the Phasemaster was 268dB and it offered a0.25dB frequency response. The distortion level amounted to 0.3 percentmax.
The system offered compatability with all present and previouslyrecorded carts. The transition could be made at the users own pacewithout 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.