AKA: Compet 30, AKA (Label): MODEL CS-31A, Product number (P/N): CS31A (CS-31A),
Keywords/Tags: CS31A (CS-31A) | 31A | Compet
Date of intro: feb-1967, Origin: Japan (List), Dimensions: 480x400x220mm, Weight: 13000g,
Power: AC,
Display: Type = Display (Nixie) (List), Brand = HITACHI: CD61 {14x}, Digits = 14, Extra Display features: Type = Display (Incandescent bulb) (List), Quantity = 2,
Number of keys: 26, #Key-Black: 4, #Key-Blue: 2, #Key-Red: 2, #Key-White: 18,
Classification: / Desktop with Display,
Featuring: Logic-technology: DTL (Diode Transistor Logic), discrete components / SSI: DTL (Diode Transistor Logic),
Related with: (Docu_Books): _Japanese, version-3,
Components: 14 PCB(s),
Main Components: SHARP: PCB with no Ref. 001; SHARP: 30APP; SHARP: 30ANo1; SHARP: 30ANo2; SHARP: 30ANo3; SHARP: 30AGP {5x}; SHARP: 30ANo9; SHARP: PCB with no Ref. 002; SHARP: 30ANo10; SHARP: 30ANo11,
Serie-members: SHARP: CS30A (No negative number representation, 100% discrete components); SHARP: CS30B (Negative number representation, 100% discrete components); SHARP: CS31A (Negative number representation, 1 PCB with early Bipolar IC's),
Known Serial-numbers: 726404 (List of all S/Ns from SHARP)
Collector value: 10/10,
Courtesy of: CALCUSEUM (Serge DEVIDTS),
Info: Although my version is holding a CS-30B Label (Black colored),
we must conclude this is probably a CS-31A milestone machine, since it's supporting a PCB with very early Bi-Polar IC's from MITSUBISHI.
Probably the first calculator supporting these IC's.
A big thanks to Rick from THE OLD CALCULATOR MUSEUM, pointing this out.
Internet: Link-1: DENTAKU MUSEUM
Intro-Sequence #: 6, Predecessor: SHARP: CS15A, Successor: SHARP: CS32A