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 YEAR: 1967
Click here for further information on our rarity scale RARITY: Exceedingly Rare Information on the rarity of this item is unknown.

Computer Trainer Model 650

A view of the vintage Computer Trainer Model 650 an important part of computer history
Developed by Irving Becker, who unfortunately died December 2005, the CT-650 was one of the earliest digital personal computers. The CT-650 is likely one of the earliest digital personal computers ever made. One could make the argument that it was the first. (Depends on how you evaluate the Minivac-601 and Minivac-6010).

Updated Oct. 2019): We are tentatively dating this computer to 1967 based on indirect evidence. The Comspace Corporation was granted a copyright for a "General Operating Manual for Arkay CT-650 computer trainer" on June 22, 1967.1 The manual is described as being for an "Arkay CT-650 desk-top computer trainer". What strikes me as odd about this is that the book upon which this computer is supposedly based was also published in 1967. Would Mr. Becker have had time to put together an operating manual?

By the 1960’s he was developing many educational products including the Computer Trainer-650 and a cardboard kit for Bell Laboratories called “CARDIAC” (a reference to its cardboard construction and the names of other kits like Brainiac and Geniac).

Irving was dedicated to education and even made a special version of the CT-650 that was made for blind students. Aside from Braille lettering, the bulbs under each light were extra strong so as to generate more heat…that way the student could “read” the results by feeling which lights were lit.

The CT-650 is sometimes called the "paperclip computer" which is a reference to a 1967 book entitled How To Build A Working Digital Computer. The book describes how to make a computer out of things one might find around the house...such as tin cans, screws, paperclips and even wooden spools of thread. The design of the CT-650 seems to have relied on the book's plans and, therefore, it is called the "paperclip computer".

The computer is 54" in length by 22" in depth. It was built for educational use with six clearly labeled sections:
  • Core Memory
  • Program Drum
  • Input Unit
  • Arithmetic Unit
  • Control Unit
  • Output Unit.
Some sources list this computer as the Arkay CT-650. The company name on the computer itself is Comspace not Arkay. But the copyright for the operating manual refers to the computer as the Arkay CT-650. Like many who were involved with early computers, Irving Becker started off in radio. In 1945, he began selling radio kits (the original name of his company was “Arkay” which stood for the “R” and the “K” in “radio kits”). By the time that this computer was offered he was in the process of changing the name of the company from Arkay to COMSPACE.

At some point before July 1980, Comspace Corporation moved from Brooklyn to Farmingdale, Long Island.

1According to the Library of Congress' Catalog of Copyright Entries: Third Series, Volume 21, Part 1, Number 2, Section 1 on page 1,690 (God bless the LOC for keeping track of information!) copyright #A925698 was issued to Comspace Corporation.

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Click on any of the images below to see the slideshow.
Front view of the CT-650.