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1981 Macintosh prototype at Computer History Museum

An early clear prototype of the first Macintosh, assembled around 1981 with an Apple II disk drive. Now at the Computer History Museum.

The first Macintosh computer system had been prototyped at Apple Computer from 1980 to 1983, prior to the release of the Macintosh 128K in January 1984.


When Jef Raskin received approval for his proposed Macintosh project in 1979, his former student Bill Atkinson recommended Apple service technician Burrell Smith for the hardware design. Smith had impressed Atkinson by adding more memory to his Apple II computer than was thought to be possible for use in the development of the Apple Lisa.[1]

George Crow and Burrell Smith with boards

George Crow (left) and Burrell Smith with the analog and logic boards that they had built for the Macintosh 128K.

Smith built the first Macintosh prototype with a Motorola 6809E processor, 64KB of RAM and a 256x256 frame buffer to Raskin's specifications. It resided on a peripheral card for the Apple II series, the only computers available for development at the time.[2] Smith was soon promoted to an engineer on the technical staff.[3] George Crow was recruited to develop the analog board, which housed the power supply and video circuitry.[4]

Around December 1980, Bud Tribble recommended that Smith adopt the more powerful Motorola 68000 processor being used by the Lisa team.[3] His first logic board design with the new processor attracted the attention of Apple co-founder Steve Jobs.[5] About half a dozen prototype boards were hand built and wire wrapped by Smith with other members of the team.[6] In 1981, Brian Howard and Dan Kottke hand assembled a clear prototype with an Apple II floppy drive. It booted into the UCSD Pascal operating system ported by Bill Atkinson as the first Mac operating system was still being developed on Lisa prototypes.[7]

Jobs assigned Jerry Manock, who had designed the Apple II's exterior case, to work on the industrial design of the Mac. Jobs signed off on the design after 6 months of work and about 50 prototype cases were produced. A signing party was held in February 1982, where the staff's signatures were gathered to be engraved inside the rear case cover of mass-produced units.[8]

Macintosh SE prototype

A transparent prototype of a Macintosh SE, which was released in 1987.

By 1983, the design of the Macintosh 128K had nearly been finalized and 8 functional prototypes had been constructed with the same 5.25" Apple FileWare drives as the Lisa. However, these drives, nicknamed "Twiggy", had a very high failure rate.[9] Crow knew about smaller 3.5-inch mechanisms that Sony had been developing, and worked behind the scenes to implement them as a replacement months before release.[10] Steve Jobs ordered the prototypes destroyed and only two have survived in working order.[9]

Apple continued the practice of creating clear prototypes of Mac models for smoke testing to observe venting in new designs.[11]


  1. Hertzfeld, Andy (1979-11). We'll See About That. Retrieved on 2019-03-10.
  2. Hertzfeld, Andy (1980-02). Scrooge McDuck.
  3. 3.0 3.1 Hertzfeld, Andy (1980-09). It's The Moustache That Matters.
  4. Geek Of The Week: George Crow by Kale, Geek Trio. 2011-10-24.
  5. Hertzfeld, Andy (1980-10). Good Earth.
  6. Macintosh Wire Wrap Logic Board #5 1980-1983, Digibarn Computer Museum. 2004.
  7. File:Early Macintosh Prototype Computer History Museum Mountain View California 2013-04-11 23-45.jpg by Victorgrigas, Wikimedia Commons. 2013-04-12.
  8. Hertzfeld, Andy (1982-02). Signing Party.
  9. 9.0 9.1 Twiggy Mac Update: World’s Oldest Working Macintosh Goes to Auction by Adam Rosen, Cult of Mac. 2013-10-30.
  10. Quick, Hide In This Closet! by Andy Hertzfeld, Folklore. 1983-08.
  11. The Proto Reserve by Hap Plain, A Little Byte Different. 2014.

See also[]

External links[]


Macintosh   Early Compact Macs

Prototypes | Macintosh 128K | 512K | 512Ke | Plus | SE | SE/30 |
Classic | Classic II | Color Classic | Color Classic II

Superseded by the Macintosh LC 500 series in June 1993