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Olympia CD 400 Technology

Electronics

Olympia CD 400
Olympia CD 400
All logic is constructed with SSI ICs, in this machine date coded from 1970. It is interesting to see a combination of US and Japanese ICs, suggesting that Japanese silicon fabrication was maturing at about this time.

  • Philco 9900 series DTL
    • 9936 Hex Inverter
    • 9946 Quad 2-input NAND
    • 9962 Quad 3-input NAND
    • 9930, 9932 Dual Expandable 4-input NAND
    • 9093 Dual J-K Flipflop
  • Matsushita 1800 series
    • These are likely to be Matsushita’s own DTL, no data has been found to date

Architecture, Memory & Speed

  • 12 display digit Nixie tubes and sign indicator lamp.
  • Digit encoding and processing to be determined.
  • Delay line memory also by Matsushita, 266.66ms total delay.
  • Master clock, memory time and full-number time to be determined.

Construction

Calculator logic is built on three double-sided PCBs.

A fourth board holds the display, display decoders/drivers and the main clock oscillator.

Keyboard is reed switch.

Power supply uses series pass regulation for main logic levels.

Construction values remain high with a diecast chassis for the electronics and careful lead dress but construction is generally more economical than first-generation machines.