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A Kenbak-1 at the Computer History Museum
Developer John Blankenbaker
Manufacturer Kenbak Corporation
Type personal computer
Release date 1971; 45 years ago (1971)
Introductory price US$750
Discontinued 1973 (1973)
Units sold 40
Units shipped 40
Memory 256 bytes of memory

The Kenbak-1 is considered by the Computer History Museum and the American Computer Museum[1] to be the world's first "personal computer".[2] Only 40 machines were ever built and sold. It was designed and invented by John Blankenbaker of Kenbak Corporation in 1970, and was first sold in early 1971. The system first sold for US$750.[3] Only 14 machines are believed to exist worldwide,[4] in the hands of various collectors. Production of the Kenbak-1 stopped in 1973[5] as Kenbak failed, and was taken over by CTI Education Products, Inc. CTI rebranded the inventory and renamed it the H5050, though sales remained elusive.[6]

Since the Kenbak-1 was invented before the first microprocessor, the machine didn't have a one-chip CPU but instead was based purely on small-scale-integration TTL chips.[7] The 8-bit machine offered 256 bytes of memory.[8] The instruction cycle time was 1 microsecond (equivalent to an instruction clock speed of 1 MHz), but actual execution speed averaged below 1000 instructions per second due to architectural constraints such as slow access to serial memory.[7]

To use the machine, one had to program it with a series of buttons and switches, using pure machine code. Output consisted of a series of lights.

See also[edit]

  • Datapoint 2200, a contemporary machine with alphanumeric screen and keyboard, suitable to run non-trivial application programs.


  1. ^[dead link]
  2. ^ "Timeline of Computer History". Computer History Museum. Retrieved July 22, 2008. 
  3. ^ "Kenbak-1 The Training Computer". Computerworld. November 17, 1971. p. 43. Retrieved May 25, 2014. 
  4. ^ "Kenbak-1". Computer Museum of Nova Scotia. Retrieved 19 November 2015. 
  5. ^ p. 52, "The First Personal Computer", Popular Mechanics, January 2000.
  6. ^ Robert R Nielsen, Snr (2005). "Inside the Kenbak-1". Retrieved 8 November 2015. 
  7. ^ a b Erik Klein. "Kenbak Computer Company Kenbak-1". Retrieved May 25, 2014. 
  8. ^ Bill Wilson (6 November 2015). "The man who made 'the world's first personal computer'". BBC News. 

External links[edit]