AKA (Label): MODEL 820SR, ELECTRONIC CALCULATOR, Product number (P/N): 820SR,
Keywords/Tags: 820SR
Date of intro: 1974, Origin: Japan (List),
Power: Rechargeable, Adaptor: CITIZEN_adaptors: CTZ800R,
Display: Type = Display (VFD) (List), Brand = FUTABA: 9CT02, Digits = 8+1,
Number of keys: 26, #Key-Blue: 13, #Key-Grey: 12, #Key-Orange: 1,
Keyboard Array (Rows x Columns): 06x05,
Miscellaneous switch: [DEG-RAD],
Classification: / Pocket,
Featuring: Scientific functions, Square root, Logic-technology: VLSI (Very Large Scale Integration), calculator-on-a-Chip,
Related with: (Docu_Articles): 1974: Kopfrechnen überflüssig,
Main Components: ROCKWELL: A4001PC,
Resemblance with: (Resemblance 008C),
Known Serial-numbers: 40401187 (404 01187) | 40613670 (List of all S/Ns from CITIZEN)
Initial Cost Price: DEM240, Collector value: 7/10,
Internet: Link-1: VIRTUAL MUSEUM OF CALCULATORS