back to ICR 412
Olympia ICR 412
Electronics
Second-generation all-SSI ICs.
Olympia ICR 412
ICs are from the Fairchild 9930 DTL logic family, made by Philco in the US and date coded from 1969
- 9093 Dual JK flipflop
- 9930 Dual 4-input Expandable NAND
- 9932 Dual 4-input Expandable buffer NAND
- 9936 Hex Inverter
- 9946 Quad 2-input NAND
- 9962 Triple 3-input NAND
Architecture, Memory & Speed
- 12 digits displayed with Nixie tubes and a sign indicator lamp
- 24-digit results can be accumulated and displayed.
- Digit encoding and processing to be determined
- Delay line memory is contained in the flat box mounted under the keyboard.
- Master clock and digit/full-number times to be determined
Construction
General construction is in keeping with second-generation machines. The case is more elegant with attention to design details but the internal construction is still quite robust. The ICR-412 has a diecast chassis that is separate from the casing and supports the circuit boards and all other components. Most interconnect wiring is handled by a printed circuit backplane and the remaining interconnects are well-made and neatly dressed.
The keyboard uses individual magnetic reed switches.