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The Answer: Rockwell Model 20R Calculator

Electronic calculator with memory and percent:

  • 8 digit LED display
  • Algebraic logic
  • Floating decimal
  • Repeat function
  • Battery operated
  • AC jack
  • Clear entry
  • Full accumulating memory
  • Automatic constants
  • % key
  • Mark-on and discount
Our exhibit has the original box and operators manual. Serial number 140550.

Manufacturer: Rockwell
Date: 1974

Other Systems Related To The Answer: Rockwell Model 20R Calculator:

Item Manufacturer Date
Rockwell Electric Printing Calculator 212P Rockwell Unknown
Rockwell 920 Rockwell International 1st January 1975
Rockwell 44RD Calculator Rockwell International 1976

This exhibit has a reference ID of CH31474. Please quote this reference ID in any communication with the Centre for Computing History.


The Answer: Rockwell Model 20R Calculator

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