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What was the first personal computer?

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Click here for further information on our rarity scale RARITY: Exceedingly Rare Information on the rarity of this item is unknown.

 YEAR: 1922
 COMPANY: Ford Instrument Company Inc.
 COUNTRY: USA
 IN OUR COLLECTION: Yes
 

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Range Keeper Mark VI

 

This unique computer is the oldest computer in our collection. An earlier version of this computer, the Mark I, was first tested on the USS Texas battleship in the summer of 1916. (Keep in mind that the US declared the "war to end all wars" on April 6, 1917.)The Navy was impressed with the performance of the Mark I and by 1917 the computer (also known as a Range Keeper) had been installed on at least four battleships... the USS New York, USS Wyoming, USS North Dakota and the USS Pennsylvania.

This computer was used to aim the guns on US Navy ships. It could calculate, in real time, an astounding number of variables for its time. It did not use any electricity!! All calculations were done by gears and the outputs were shown on the display.

The metal label attached to this item makes clear that, as far as the Navy was concerned, it was a computer. Later versions of this computer were commonly referred to as Range Keepers. The label is somewhat difficult to read but you should make out the following:

U.S. NAVY BUREAU OF ORDNANCE
COMPUTER
MARK VI MOD.7 SER. NO. 656
INSPR. (US Anchor stamp) DATE ___ WT 103 LBS
5" - 38 CAL 2500 F.S.I.V.
O.P. 551 ORD SK 61190
manufactured by
INTERNATIONAL BUSINESS MACH CORP
Endicott, New York
LICENSED BY FORD INSTRUMENT CO INC.

This mechanical analog computer was made completely of gears. This computer determined how the big guns on the ship were to be aimed at the enemy ships. It was designed to be bolted to the deck of a Navy ship and actually had a sight vane built into the computer to determine the enemy target relative angle. All data was entered by a sailor or sailors standing around it.

This analog computer used only hand operated inputs (mechanical). All the data used for computing the firing position for the big guns had to be set up by hand, generally by turning knobs or handles that would, in turn, move gears within the computer. The Mark VI had seven knobs (Wind Speed, Ship Speed, Target Speed, Target Angle, Wind Angle, True Bearing, Deflection Correction) and turning each one would set the internal gears so that a firing solution could be computed. The settings could be monitored by the operator simply by looking at a series of dials on the computer display. (The operator stood and looked down through a glass top, beneath which were the current settings for the computer.) There were also handles that needed to be set.

We have tentatively dated this analog computer to 1922 while we complete our research. The National Museum of the United States Navy in Washington, DC has informed us that they do not have any records that allow them to track the serial number of the computer.

We hope that the images of this analog computer provide you with a new perspective on computing and an appreciation for the ingenuity of those men and women who developed this computer. We are used to seeing computer boards and wires in a computer...but to realize that the decision making (firing solution) was done by gears is really quite amazing.

This Range Keeper seems to be the most complete example in existence. It even includes the stand the was bolted to the deck of the ship and held the computing unit high enough for sailors to enter data. The model in our collection is missing the sight vane that allowed the sailors to manually located the enemy vessel.


Related Items
      Related Item 1: Range Keeper Mk. 7
      Related Item 2: Time of Flight Clock
      Related Item 3: Fire Control Equipment: Range Keeper Mark VII





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IMAGES
Click on any of the images below to see the slideshow. Side View of Mark VI Computer and support stand Top View of Computer Close up of Navy identification tag
COMPUTER COLLECTION LIST (PRE-1981)
(Analogs in blue)
  1. AIM-65 (single board)
  2. AIM-65 (factory case)
  3. AIM-65 (Jon Titus)
  4. ALICE micro-ordinateur
  5. Altair 680
  6. Altair 8800
  7. Altair 8800A
  8. Altair 8800b
  9. Altair 8800b Turnkey (see Pertec below)
  10. Altair 8800b (see Pertec below)
  11. Altair 8800b w/ Hardisk Controller & Datakeeper
  12. Altos ACS-8000
  13. American Basic Science Club Analog Computer
  14. AMF Educational Computer
  15. Apple II Plus
  16. ASCI SystemX
  17. ASR 33 Teletype
  18. Automatic Teaching Computer Kit
  19. Beckman ElectroComp Electric Heating Computer
  20. Beckman ElectroComp Energy Savings Computer
  21. Beckman Solid State Fuel Cost Computer
  22. Brainiac K-30
  23. Calif. Computer Systems 2200
  24. CES Ed-Lab 650
  25. Commodore 8032
  26. Commodore 64
  27. Commodore PET 2001
  28. Commodore Super Pet
  29. Compucolor II
  30. Compukit 1
  31. Compukit 1 Deluxe Model
  32. Compukit 2
  33. Compukit UK101
  34. Comspace CT-650
  35. Cosmac Elf (RCA1802)
  36. Cosmac Microtutor
  37. Cosmac Netronics ELF II
  38. Cosmac VIP
  39. Cromemco System I
  40. Cromemco System III
  41. Cromemco Z-2D
  42. Datapoint 2200
  43. Digi-Comp I (flat box)
  44. Digi-Comp I (square box)
  45. Digital Computer Lab
  46. Donner 3500
  47. Durango F-85
  48. Dynabyte
  49. E & L Inst MMD-1
  50. E & L Inst MMD-2
  51. Eagle II
  52. Electric Tabulating Machine (one original counter, 1889)
  53. Electronic Associates TR-10
  54. Electronic Associates TR-10 Model II
  55. Electronic Associates TR-20
  56. Electronic Associates TR-48
  57. Electronic Associates Model 180
  58. Electronic Associates Model 380 Hybrid
  59. Geniac
  60. Google Glass (definitely not vintage)
  61. Heath EC-1 (factory assembled by Heath)
  62. Heathkit EC-1 (kit)
  63. Heathkit ET 3100 trainer
  64. Heathkit H8
  65. Heathkit H9 Video Terminal
  66. Hickok Logic Teaching Sys.
  67. Hickok Servo Teaching Sys.
  68. HP 2115A
  69. HP 85
  70. HP 5036A
  71. HP 9825A
  72. HP 9825B
  73. HP 9830A
  74. Iasis 7301
  75. I-COR MAC-1
  76. ICS Microcomputer Training System
  77. IMSAI 108 (prototype)
  78. IMSAI 8048 Control Computer
  79. IMSAI 8048 (The Dollhouse Computer)
  80. IMSAI 8080
  81. IMSAI PCS-40
  82. IMSAI PCS-80
  83. IMSAI VDP-80
  84. Informer
  85. Intel Intellec MDS
  86. Intel MDS-800
  87. Intel Prompt 48
  88. Intel SBC 80/10
  89. Intel SDK-85
  90. Intel SDK-85 (unassembled)
  91. Intel SDK-86
  92. Intertec Superbrain
  93. ITT MP-EX
  94. JR-01 Computer
  95. KIM-1
  96. LAN-DEC
  97. LAN-DEC 20
  98. LAN-ALOG
  99. Lehrcomputer (Germany)
  100. Lawrence Livermore Lab
  101. Lear Siegler ADM3A
  102. Logikit LK255 (Feedback)
  103. Logix SF-5000 Electronic Computer
  104. MAC-1 Mini Analog Computer
  105. MAC Tutor (Bell Laboratories)
  106. MEK6800D2
  107. Micro 68
  108. Microtan 65
  109. Midwest Scientific Instruments 6800
  110. Minivac 601
  111. Minivac 6010
  112. Mini-Scamp Microcomputer
  113. Nascom I
  114. Nascom II
  115. National Radio Institute 832
  116. NEC TK-80
  117. NorthStar Horizon
  118. Olivetti Programma 101
  119. Olivetti Programma 203
  120. Olivetti Programma 602
  121. Open University PT501
  122. Ordinateur d'Apprentissage JR-01
  123. Osborne 1
  124. OSI 300
  125. OSI 600 (SuperBoard II)
  126. OSI C2-OEM-4
  127. OSI Challenger-1P
  128. Pastoriza Personal Analogue Computer
  129. Pertec MITS 300/25 (Altair desk business system)
  130. Pertec MITS 300/55 (Altair Turnkey business system)
  131. PolyMorphic Systems 8810
  132. PolyMorphic Poly-88
  133. Protech-83
  134. Range Keeper Mk.6 Mechanical Analog Computer, 1926
  135. Range Keeper Mk.7 Mechanical Analog Computer, 1935?
  136. Sargent-Welch Scientific Company Cat. No.7528 Analog Computer
  137. Science of Cambridge MK-14 (Sinclair)
  138. SD Systems Z80 starter kit
  139. Sharp MZ-40K
  140. Sharp MZ-80k
  141. Siemens ECB-85
  142. Signetics Instructor 50
  143. Sinclair ZX-81
  144. Smoke Signal Broadcasting
  145. Sol-20
  146. Spark16
  147. Sphere 1
  148. Sphere/SWTPC Computer System
  149. SWTP CMOS Microlab
  150. SWTP CT-82 Terminal
  151. SWTPC 6800
  152. SWTPC 6800 (w/ Smoke Signal Broadcasting drive)
  153. SWTPC CT-64 Video Terminal, SS-50
  154. SWTPC TV Typewriter II CT-1024
  155. Synertek VIM-1
  156. Synertek SYM-1
  157. Systron-Donner 3500
  158. Tei MCS-112
  159. Tektronix 4006-1
  160. Telefunken RAT 700
  161. TI LCM-1001 (Microprogrammer)
  162. TI LCM-1001 (Microprogrammer)
  163. TI Silent 700 Terminal
  164. TI TM 990/189
  165. Vector 1
  166. Vector 3
  167. Vidac 336
  168. Wang 2200
  169. Welch Scientific Company Cat. No.7528 Analog Computer
  170. Xerox 820 Mark I
OTHER COMPUTERS (LUGGABLES 1982-1986)
  1. Chameleon Plus
  2. Commodore SX64
  3. Epson HX-20
  4. Kaypro I
  5. Kaypro II
  6. Kaypro 2x
  7. Kaypro 16
  8. Osborne 1
  9. Panasonic Senior Partner
  10. Visual Commuter
RARE & NOTABLE DOCUMENTS
  1. Babbage's Calculating Engine (1834)
  2. Electric Tabulating Machine (1889, Herman Hollerith's personal copy)
  3. The Hollerith Electric Tabulating System (1890)
  4. Counting a Nation by Electricity (1891)
  5. Calculating Machines (1947)
  6. Moore School Lectures Vol. II (1947)
  7. Mathematical Theory of Communication (1948)
  8. Communication Theory of Secrecy Systems (1949)
  9. The "Moore's Law" article (Electronics, 1965)
  10. Printout from Babbage's Difference Engine #2 (London Science Museum, 2004)