Impressions of Analog Computers

This page contains a variety of analog computer impressions - most of these machines have been scrapped a long time ago (which really makes me feel sad). Where ever possible picture sources are cited, but in many cases I have no idea where the pictures came from. I hope that I do not violate any ones copyright with this collection of pictures. The pictures are shown for academic purposes only to keep these machines from getting forgotten.

I you have pictures of analog computers not shown here, please send them to ulmann@analogmuseum.org.

This picture shows a master/slave configuration of two transistorized MEDA analog computers. This series was designed and built in Prague (former Czechoslovakia).

A series of pictures of two MEDA 42 analog computers (thanks to A. Shenshyn for these wonderful pictures): 1, 2, 3, 4, 5, 6, 7, 8, 9.

Beckman EASE 1032 analog computer as it was used by the Bonneville Power Administration to gain insight into stability questions of large power grids (cf. "Bonneville Power Administration Solves Swing Equations with EASE", in "Instruments and Automation", March 1957, p. 498).

A Beckman EASE 1132 electronic analog computer as it was used in the Beckman/Berkely Computation Center that opened its doors on February 28th, 1958 in Los Angeles (cf. "Instruments and Automation", February 1958, p. 288).

Beckman EASE 2132.

Rather gigantic EASE 2133 installation at the MBB (Messerschmitt Bölkow Blohm - a large German aerospace company) computer center (cf. "MBB Simulation", Firmenschrift Messerschmitt Bölkow Blohm GmbH, Unternehmensbereich Flugzeuge).

Richard FithHugh solves the Hodgkin-Huxley equations using a Beckman analog computer (source: Izhikevich E. M., FitzHugh R.).

A function generator, based on a servo driven multi slider potentiometer developed by Bell. Function generators like this were used in fire control systems and the like.

Bendix G15-D digital computer with attached Digital Differential Analyzer (cf. Martin L. Klein, Frank K. Williams, Harry C. Morgan, "Digital Differential Analyzers", in "Instruments and Automation", June 1957, p. 1105).

Bendix D-12 Digital Differential Analyzer (cf. "Bendix Computer - Digital Differential Analyzer D-12", Bendix Computer, 5630 Arbor Vitae Atreet, Los Angeles 45, California, p. 2).

Scale model of the large hybrid computation facility which was installed at the Lockheed Missile and Space Company (cf. George A. Bekey, Walter J. Karplus, "Hybrid Computation", John Wiley & Sons, Inc., 1968, p. 166).

Hybrid computer installation at the Naval Postgraduate School (end of the 1960s) consisting of a SDS 9300 digital computer and a COMCOR CI 5000 analog computer (photo: Bob Limes).

COMCOR INTRACOM CI-5100 (cf. George A. Bekey, Walter J. Karplus, "Hybrid Computation", John Wiley & Sons, Inc., 1968, p. 168).

The tube based ELARD analog computer that was developed at the TU Darmstadt (Germany).

The Dornier 240 analog computer - as far as I know this machine is based on a very similar (identical?) machine built by Simulators Inc. (Could someone confirm this?) This machine was once in use at the Institut für Mess- und Regelungstechnik of the University Karlsruhe but has been scrapped.

The Dornier 720 analog computer - as far as I know this machine, too, is based on a very similar (identical?) machine built by Simulators Inc. (Could someone confirm this?)

The EAI Pace 96 analog computer that was installed in the first europaean analog computer center in Brussels in 1957 (cf. "Eröffnung des ersten europäischen Analog-Rechenzentrums", in "Elektronische Rundschau", August 1957, 11. Jahrganh, Heft 8, p. 253).

A wonderful triple Pace 16-31R installation (right hand side) with optical function generators (cylindrical objects in the background) and various support equipment. Unfortunately I managed to forget where this photo came from.

EAI analog computer at the DLR (Deutsches Zentrum für Luft- und Raumfahrt) - what model is this? (Picture source: Dr. Jessika Wichner, DLR, signature FF-756.)

EAI 231R analog computer (with gaussian noise generator and readout printer).

A late model of EAI's highly successful tube based EAI 231 analog computer. Note the digital expansion unit on the left (above the table plate).

A rather large installation of two EAI 231R analog computers with additional devices such as plotters, function generators, multipliers and the automatic setup system ADIOS - far right (cf. "PACE 231R analog computer", Electronic Associates, Inc., Long BRanch, New Jersey, Bulletin No. AC 6007).

A large EAI 231R analog computer installation.

Closeup of the removable patch field of an EAI 231R analog computer (cf. "PACE 231R analog computer", Electronic Associates, Inc., Long BRanch, New Jersey, Bulletin No. AC 6007, p. 6).

The EAI 231R installation at the Deutsches Elektronensynchrotron in Hamburg (picture: Inge Borchardt). This system was mainly used to develop the magnetic lenses for the electron accelerator. Other projects involved the development of the power supplies for the accelerator etc.

Bell developed this simulator for project Mercury which was based on an EAI 231R analog computer (cf. M. D. Fagen (Ed.), "A History of Engineering and Science in the Bell System - National Service in War and Peace (1925 - 1975)", Bell Telephone Laboratories, Inc., p. 569).

The Tactical Avionics System Simulator, TASS, about 1968 (photo: Bruce Baker).

EAI 231R installation (photographer Colin Adby, thanks to James Miller).

EAI 231R installation (photographer Colin Adby, thanks to James Miller).

Analog computer installation at the DLR (Deutsches Zentrum für Luft- und Raumfahrt). From left to right: Multichannel display (with electronic axis-diplay), EAI-231RV (full complement of components), EAI-231R (fully expanded, too), EAI-231RV (about one half of the components are installed) on the right. (Picture source: Dr. Jessika Wichner, DLR, signature FF-757.)

A wonderful EAI 231 computer (picture: Wolfgang Strobl).

Analog computer installation at the DLR (Deutsches Zentrum für Luft- und Raumfahrt). The half populated EAI-231RV is now on the left, followed by another fully equipped EAI-231RV in the middle and a fully equipped EAI-231R on the far right. (Picture source: Dr. Jessika Wichner, DLR, signature FF-557.)

The HYDAC 2000 installation in the EAI computer center in Brussels (cf. "Electronic Associates, Inc., Europäisches Rechenzentrum für Analog- und Hybridrechentechnik", in "Elektronische Rechenanlagen", 6 (1964), Heft 4, p. 214).

EAI PACE installation at Convair.

Early picture of an EAI TR-10 table top analog computer.

EAI TR-10 table top analog computer at the TU Darmstadt.

This picture shows Dr. Willi Frisch in about 1964 working on his diploma thesis with an EAI TR-10 table top analog computer at the TU Darmstadt (photo: Dr. Willi Frisch).

This is another picture showing Dr. Willi Frisch in about 1964 working on his diploma thesis with an EAI TR-10 table top analog computer at the TU Darmstadt (photo: Dr. Willi Frisch).

The ray tracer of Light, Badger and Barnes, based on an EAI TR-10 transistorized table top analog computer (cf. L. Light, J. Badger, D. Barnes, "An Automatic Acoustic Ray Tracing Computer", in "IEEE Transactions on Electronic Computers", Vol. EC-15, No. 5, October 1966, p. 724).

EAI TR-48 table top analog computer.

Partially populated EAI TR-48 table top analog computer (background left) and PDP-11 on the right (11/20?).

An EAI 380 transistorized analog computer.

An EAI 580 transistorized analog computer. This particular machine was once used at the Institut für Mess- und Regelungstechnik of the University Karlsruhe and is now part of the collection of the Analog Computer Museum.

An EAI 680 transistorized analog computer.

A wonderful operator's desk for an EAI 680 analog computer. Note the electronically generated grid on the large screen oscilloscope display in the middle.

EAI MiniAC - a small table top transistorized analog computer.

EAI MiniAC - a small table top transistorized analog computer.

A rather large EAI Pacer hybrid computer installation - the rack on the left holds the digital processor.

Yet another EAI Pacer hybrid computer installation.

And another EAI Pacer hybrid computer installation. The stand alone rack on the left contains the AD/DA-converters and the necessary control logic to interface the digital processor with the analog computer.

EAI curve follower. This device was based on a conventional X/Y-plotter which was extended with a pickup and a small servo circuit that allowed the plotter to follow a trace painted on paper representing the function desired.

EAI delay line, used to simulate processes with a time lag.

When one joined the EAI Computer User's Group, one got this rather pretty certificate. :-)

The GEDA (Goodyear Electronic Differential Analyzer) Power Dispatch Computer (cf. "New GEDA Power Dispatch Computer", in "Instruments and Automation", Vol. 30, Feb. 1957, p. 157).

Richard Day runs a inertia-coupling simulation which was implemented on GEDA analog computers (NASA photo E-1841).

Installation of GEDA analog computers at NACA, October 1956 (NASA photo E-2626).

This is a picture of the first electronic analog computer developed and built by Dr. Helmut Hoelzer in Peenemünde as it was used after WWII at the Redstone Arsenal (source: Marshall Space Flight Center).

This picture shows the so called Mischgerät - world's first fully electronic on-board computer that was used to guide the A4 rocket (photo: Adri de Keijzer).

In 1959 the development of the EARI (short for "Elektronische Analogierechenanlage Ilmenau") was completed at the "Institut für Physik" of the "Hochschule für Elektrotechnik Ilmenau in the German Democratic Republic. This machine consisted of 16 operational amplifiers, seven quad-potentiometer units, seven drawers with two adders each, five multipliers, six inverters, three oscilloscopes, two compensating voltmeters, three special function generators etc. (cf. this paper).

This picture shows a top view of the "Fahrdiagraph" developed by Udo Knorr (patented in 1920) This device was a true differential analyzer with feedback and predates the machines developed by Vannevar Bush (picture source: Dr. Ralf Bülow).

Side view of the "Fahrdiagraph".

The production model of MADDIDA used in the Navy Electronics Laboratory (NEL, File Number E1278).

The Packard Bell TRICE DDA, a so called Digital Differential Analyzer - a digital analog computer (cf. W. Ameling, "Aufbau und Arbeitsweise des Hybrid-Rechners TRICE", in "Elektronische Rechenanlagen", 5 (1963), Heft 1, p. 30).

Closeup of a multiplier module of the Packard Bell TRICE DDA, a so called Digital Differential Analyzer - a digital analog computer (cf. W. Ameling, "Aufbau und Arbeitsweise des Hybrid-Rechners TRICE", in "Elektronische Rechenanlagen", 5 (1963), Heft 1, p. 30).

Philbrick analog computer installation at the Pullman-Standard Car Manufacturing Company (cf. Jerry Roedel, "History and Nature of Analog Computors", in Henry M. Paynter (Ed.), "A Palimpsest on the Electronic Analog ARt", printed by Geo. A. Philbrick Researches Inc., AD 1956, p. 488).

The ENDIM 2000 analog computer was a tube based design developed and manufactured in the former German Democratic Republic at "Rechenelektronik Glashütte". About 20 machines were produced - only one seems to have survived at the Technische Sammlungen Dresden. A maximum configuration contained 64 chopper stabilized amplifiers (32 integrators/summers + 32 summers), 12 multipliers, 16 function generators and 90 coefficient potentiometers (cf. this paper).

This picture of an ENDIM 2000 analog computer is from the Universität Halle.

ENDIM 2000 with peripheral units in operation (this picture was taken from here).

Special purpose oscilloscope for the ENDIM 2000 analog computer.

REAC analog computer with automatic setup feature.

Control desk of the GEPUS analog computer (cf. C. A. A. Wass, "Introduction to Electronic Analogue Computers", London, Pergamon Press Ltd., 1955, p. 209).

Control room of the TRIDAC analog computer (cf. C. A. A. Wass, "Introduction to Electronic Analogue Computers", London, Pergamon Press Ltd., 1955, p. 214).

Overall structure of the TRIDAC analog computer (cf. C. A. A. Wass, "Introduction to Electronic Analogue Computers", London, Pergamon Press Ltd., 1955, p. 214).

Swash plate based function generator for trigonometric functions as used in the TRIDAC analog computer (cf. C. A. A. Wass, "Introduction to Electronic Analogue Computers", London, Pergamon Press Ltd., 1955, p. 214).

Tube based Solartron Minispace analog computer.

Tube based Solartron Tutor analog computer with only five chopper stabilized operational amplifiers and eight coefficient potentiometers.

In 1956 Space Technology Laboratories delivered the first so called ADDAVERTER - a multichannel D/A-/A/D-converter which was used to build hybrid computers out of an analog computer and a digital processor. The ADDAVERTER shown here has 15 A/D- and 10 D/A-channels with a range of +/- 100 V and a precision of 0.1 percent. The picture was taken out of "Combined Analog and Digital Systems - Why, When and How" by John H. McLeod and Robert M. Leger, published in "Instruments and Automation", June 1957, p. 1129.

Front view of the very first electronic analog computer built by Telefunken - the RA 1.

Telefunken RA 463 analog computer in its minimum configuration.

Nuclear reactor simulator, based on a Telefunken RA 463 analog computer (cf. Robert Gerwin, "Atom-Strom für deutsche Städte", in "Hobby - Das Magazin der Technik", Nr. 9, September 1958).

Telefunken RA 463/2 analog computer in its maximum configuration (cf. "Elektronischer Analogrechner RA 463/2", Telefunken, AH 5.2, April 1958).

Telefunken RA 463/2 analog computer (picture source: http://commons.wikimedia.org/wiki/File:TMW_Analogrechner_Telefunken.jpg).

First prototype of a fully transistorized electronic analog computer made by Telefunken (late 1950s - before EAI developed the TR-10 and TR-20) (cf. Dietrich Ernst, "Elektronische Analogrechner - Wirkungsweise und Anwendung", R. Oldenbourg Verlag München, 1960, p. 255).

In 1959 Telefunken brought the world's first fully transistorized table top analog computer to the market. This machine, the RAT 700 was to become the first of a large family of transistorized analog computers developed by Telefunken, eventually leading to the RA 770 precision analog computer.

This picture shows Mr. Winkler, an engineer of the "Laboratory Walter" with the Telefunken RAT 700 table top analog computer (cf. Robert Gerwin, "Intelligente Automaten", Chr. Belser Verlag, 1964, p. 84).

In 1965 the German "Hobby"-magazine published an article about a mass-spring-damper simulation that was shown at a large exhibition in Germany. This simulation was a true eye catcher and resulted in quite some sales for Telefunken (more about this particular simulation can be found here.

Telefunken RA 710 table top analog computer.

Telefunken RA 742 table top analog computer.

Telefunken precision analog computer RA 800 in its minimal configuration (cf. G. Meyer-Brötz, "RA 800 - Ein transistorisierter Präzisions-Analogrechner", in "Telefunken Zeitung", Jg. 33 (September 1960), Heft 129, p. 176).

Drawer containing 30 high precision, chopper stabilized operational amplifiers, used in the Telefunken RA 800 (cf. G. Meyer-Brötz, "RA 800 - Ein transistorisierter Präzisions-Analogrechner", in "Telefunken Zeitung", Jg. 33 (September 1960), Heft 129).

Closeup of the removable patch panel of a Telefunken RA 800 (cf. G. Meyer-Brötz, "RA 800 - Ein transistorisierter Präzisions-Analogrechner", in "Telefunken Zeitung", Jg. 33 (September 1960), Heft 129).

Telefunken precision analog computer RA 800 (cf. Adolf Kley, "Analogrechner", in Helmar Frank (Ed.), "Kybernetische Maschinen", R. Oldenbourg Verlag München, Wien, 1968, p. 133).

This picture shows a remarkable installation at a Telefunken laboratory in the early 1960s. On the right is a minimum configuration RA 800 precision analog computer which is supported by five RAT 700 table top computers sitting on the desks on the left (each of these computers weighs about 100 kg!). In addition to that there is a digital voltmeter on top of the third RAT 700 and a small oscilloscope (Tektronix?) next to the RA 800.

Telefunken Hybrid computer RA 800H (cf. Helmut Adler, "Elektronische Analogrechner", VEB Deutscher Verlag der Wissenschaften, Berlin, 1968, p. 273).

Promotion picture of a Telefunken RA 770 precision analog computer.

Promotion picture of a Telefunken RA 770 precision analog computer.

Promotion picture of a Telefunken RA 770 precision analog computer.

Promotion picture of a Telefunken RA 770 precision analog computer with annotations.

This picture shows a rather rare setup of a Telefunken RA 770 precision analog computer. The two racks on the right side of the picture are the so called RA 775 - in fact a second RA 770 but without the control logic etc. This extension acted as a slave computer to the main RA 770. A maximum configuration would consist of one RA 770 with two RA 775 extensions giving all in all about 600 operational amplifiers. You will note that the picture has been poorly edited by hand where the oscilloscope is mounted. This was caused by the fact that Telefunken stopped the production of its own OMS 811 special purpose oscilloscope and started shipping its analog computers with slightly modified storage oscilloscopes made by HP - that's the oscilloscope that has been edited into the photo.

Promotion picture of a Telefunken HRS860 hybrid computer system consisting of a RA 770 precision analog computer and a Telefunken TR-86 digital computer.

Promotion picture of a Telefunken HRS860 hybrid computer system consisting of a RA 770 precision analog computer and a Telefunken TR-86 digital computer (cf. "Kurzbeschreibung - Hybrides Rechensystem HRS 860", AEG-TELEFUNKEN, Fachbereich Informationstechnik, N41 AC 52 0473).

The Telefunken RA 770 that was once installed at the Deutsches Elektronensynchrotron in Hamburg. This shot was taken during an open house ceremony (picture: Inge Borchardt).

Promotion picture of a Telefunken electronic resolver ERS 801.

Promotion picture of a Telefunken time delay unit LZG 102.

Promotion picture of a Telefunken non-linear functions unit NNT 740.

Early version of the non-linear functions drawer as used in the Telefunken RA 800 precision analog computer.

The first five digit digital voltmeter made by Telefunken for its RA 800 precision analog computer.

Drawer containing four five-channel time division multipliers.

Telefunken random noise generator RGF 104.

ALPAM S 200 (picture source: http://interstices.info/jcms/c_33558/les-calculateurs-analogiques)

Tube based analog computer built by Valvo in 1957.

Closeup of the patch field of the Valvo analog computer shown above.

In the late 1950s/early 1960s the "Wissenschaftlich-Technische Büro für Gerätebau" in east Berlin developed the UNIMAR - a tube based analog computer that was used mainly for the simulation of control systems.

This picture shows a small analog steering simulator (cf. John H. McLeod, Suzette McLeod, "The Simulation Council Newsletter", in "Instruments and Automation", Vol. 31, Dec. 1958, p. 1995).

A function generator used in an analog computer for flight simulation.

Small russian analog computer BPRR-2 - this machine was used to solve optimization problems in industrial processes (cf. V. B. Ushakov, "Soviet Trends in Computers for Control of Manufacturing Processes", in "Instruments and Automation", Dec. 1958, p. 1961).

Large scale russian special purpose analog computer ZI-S used to solve questions in the field of hydraulics (cf. V. B. Ushakov, "Soviet Trends in Computers for Control of Manufacturing Processes", in "Instruments and Automation", Nov. 1958, p. 1812).

Very small russian MN7 table top analog computer (I would love to learn more about this machine - please let me know if you have any information about it). The patch field is hidden under the top lid of the computer, so during normal operation the setup can not be changed accidentally.

Small russian MN10M table top analog computer (I would love to learn more about this machine - please let me know if you have any information about it).

Large russian analog computer MN17M (I would love to learn more about this machine - please let me know if you have any information about it).

The Electronic Analog Frost Computor, a direct electronic analog computer, developed by the US Army Corps of Engineers, New England Division (cf. H. P. Aldrich, H. M. Paynter, "First Interim Report - Analytic Studies of Freezing and Thawing of Soils (for the Arctic Construction and Frost Effects Laboratory, New England Division, Corps of Engineers)", in Henry M. Paynter (Ed.), "A Palimpsest on the Electronic Analog ARt", printed by Geo. A. Philbrick Researches Inc., AD 1956, p. 259).

HETAC, the Heat Exchange Transient Analog Computer (cf. "University Research Instrumentation", in "Instruments and Automation", June 1957, p. 1120).

Analog computers at a NASA simulation facility during the development of the control stick for project Mercury.

The Nike-Resarch-and-Development analog computer in 1951 (cf. M. D. Fagen (Ed.), "A History of Engineering and Science in the Bell System - National Service in War and Peace (1925 - 1975)", Bell Telephone Laboratories, Inc., p. 383).

The Nike-Resarch-and-Development analog computer in 1951 with covers opened (cf. M. D. Fagen (Ed.), "A History of Engineering and Science in the Bell System - National Service in War and Peace (1925 - 1975)", Bell Telephone Laboratories, Inc., p. 383).

A plotter based quad function generator for functions of the form f(x, y) - the paper is conductive and the function is represented by potential field generated by silver paintings on the paper.

Mechanical tides computers (Fourier synthesizer), picture source: Dr. Ralf Bülow.