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Pioneercomputertimeline2.Pdf
Memory Size versus Computation Speed for various calculators and computers , IBM,ZQ90 . 11J A~len · W •• EDVAC lAS• ,---.. SEAC • Whirlwind ~ , • ENIAC SWAC /# / Harvard.' ~\ EDSAC Pilot• •• • ; Mc;rk I " • ACE I • •, ABC Manchester MKI • • ! • Z3 (fl. pt.) 1.000 , , .ENIAC •, Ier.n I i • • \ I •, BTL I (complexV • 100 ~ . # '-------" Comptometer • Ir.ne l ' with constants 10 0.1 1.0 10 100 lK 10K lOOK 1M GENERATIONS: II] = electronic-vacuum tube [!!!] = manual [1] = transistor Ime I = mechanical [1] = integrated circuit Iem I = electromechanical [I] = large scale integrated circuit CONTENTS THE COMPUTER MUSEUM BOARD OF DIRECTORS The Computer Museum is a non-profit. Kenneth H. Olsen. Chairman public. charitable foundation dedicated to Digital Equipment Corporation preserving and exhibiting an industry-wide. broad-based collection of the history of in Charles W Bachman formation processing. Computer history is Cullinane Database Systems A Compcmion to the Pioneer interpreted through exhibits. publications. Computer Timeline videotapes. lectures. educational programs. C. Gordon Bell and other programs. The Museum archives Digital Equipment Corporation I Introduction both artifacts and documentation and Gwen Bell makes the materials available for The Computer Museum 2 Bell Telephone Laboratories scholarly use. Harvey D. Cragon Modell Complex Calculator The Computer Museum is open to the public Texas Instruments Sunday through Friday from 1:00 to 6:00 pm. 3 Zuse Zl, Z3 There is no charge for admission. The Robert Everett 4 ABC. Atanasoff Berry Computer Museum's lecture hall and rece ption The Mitre Corporation facilities are available for rent on a mM ASCC (Harvard Mark I) prearranged basis. For information call C. -
Chapter Six: Relay Calculators
200 Chapter 6 Relay Calculators Introduction harles Babbage had planned to power his Analytical Engine Cwith a steam engine-steam being the only feasible prime mover available in the 1830s. In that same decade, however, others were making discoveries that led to the electric motor: a source of motive power more compact, cleaner, quieter, and most of all, much more flexible than steam. By the early twentieth century, calculators were just one of many machines that were powered by electricity. But electricity could do more than replace the steam engine or human arm as a source of power; it could also represent the numbers themselves that a calculator handles. Electric circuits could replace the cams, pins, gears, and levers that actually do the computation. Hollerith’s electric tabulators took advantage of this property, and we have already seen how the rival Powers system, developed after 1911 to compete with Hollerith, suffered in comparison because it used electricity only for motive power. By the 1930s, a number of inventors recognized that the ability (as well as the power) offered by electric circuits allowed one to build a machine that could not only do arithmetic, but also direct a complex -ce of calculations autom&@ly. Thime,had be& Babbage’s drezand bmatdreGhad come true. It came true by combining traditional mechanical calculator architecture with 201 FIXED ENDS F MIL OF WIRE’ IRON ,Ad (1 NO SIGNAL VOLTAGE ON d -COIL TERMINALS OPEN CIRCUIT - NO CURRENT ELECTROMAGNETIC RELAY la] DE- ENERGIZED ELECTROMAGNETIC RELAY lbl ENERGIZED Figure 6.1. (a) Typical relay used in telephone switching. -