AKA: MEMO NOTE 30, LIQUID CRYSTAL CALCULATOR LC-836MN, AKA (Label): ELECTRONIC CALCULATOR, MEMO-NOTE LC-838MN, Product number (P/N): LC836MN (LC-836MN),
Keywords/Tags: LC836MN (LC-836MN) | MEMO NOTE 30 | LIQUID CRYSTAL CALCULATOR
Date of intro: ~10-may-1978, Origin: Japan (List), Dimensions: 138x68x8mm, Weight: 85g,
Power: Button: (x3),
Display: Type = Display (LCD yellow) (List), Digits = 8+1,
Number of keys: 30,
Keyboard Array (Rows x Columns): 06x05,
Classification: / Pocket / Data,
Featuring: Procent, Square root,
Related with: TOSHIBA_docu: (Cat.) 198107 (J); TOSHIBA_docu: (Instr.) LC836MN; TOSHIBA_docu: (Ad.) *: Les cristeaux liquides, la nouvelle...; TOSHIBA_docu: (Ad.) LC836MN: Sensationelle...; TOSHIBA_docu: (Ad.) *: Votre mémoire...; TOSHIBA_docu: (Broch.) LC836MN (J); TOSHIBA_parts: (Box) LC836MN,
Known Serial-numbers: C54616 | L51870 (List of all S/Ns from TOSHIBA)
Initial Cost Price: 16000 JPY (€ 129,60), Collector value: 8.5/10,
Courtesy of: CALCUSEUM (Serge DEVIDTS),
Info: The LC-836MN (also known as the Memo Note 30) represents a major milestone in technology as the world's first pocket-sized electronic data bank.
By combining an alphanumeric storage system with a traditional calculator, it fundamentally changed how people managed personal information.
This innovative device introduced digital organizing features nearly a decade before rivals like TEXAS INSTRUMENTS entered the mini data bank market.


his device did not just calculate numbers; it was the world’s very first handheld electronic data bank.
It proved that alphanumeric data could be stored and retrieved on a pocket-sized budget.


Achieving non-volatile alphanumeric storage in 1978 required highly specialized silicon.
While competitors were strictly manufacturing basic four-function calculators,
TOSHIBA engineered a proprietary dual-chip system
T3690:
This main CPU handled keyboard scanning, basic arithmetic operations, and multiplexing for the display.
T3691:
A dedicated CMOS RAM chip holding exactly 2,048 bits (256 bytes) of data.

With only 256 bytes of available memory, storing data required extreme optimization.
TOSHIBA engineers bypassed complex file systems by hardcoding a strict memory-partitioning architecture.


In Number Mode, the device operated as a standard arithmetic calculator.
Sliding the switch to Letter Mode remapped the matrix keyboard, allowing users to scroll sequentially through the 30 registers, edit names, and input telephone numbers.
This simple mechanical toggle laid the conceptual groundwork for the multi-mode software interfaces we use today.
Internet: Link-1: DATAMATH CALCULATOR MUSEUM