Tatung 71739

Tatung 71739
Manufacturer	Tatung
Layouts	93-key standard typewriter format
Keyswitches	Alps SKCC Cream
Keycaps	Double-shot moulding
Weight	1525 g
Years of production	1984

The Tatung 71739 keyboard was part of the Tatung TPC-2000 computer released in 1984 which was Tatung's small business oriented follow up to their home computer system Einstein.

The TPC-2000 detachable keyboard has been designed with ease of use in mind. It has 93 sculptured keys arranged in standard typewriter format, and includes alpha lock, 18-key numeric pad with decimal and 6 programmable function keys which can be used to implement automatically complicated and repetitive operation with a single key stroke. The keyboard layout is documented in page 49 of the manual (see documentation below).

The construction of the feet and the mechanism is unusual and quite poor compared to the rest of the keyboard. The feet are rotated outwards by pressing and rotating the round "buttons" on either side of the keyboard. The beige function key and the grey alpha double-shots have a structured surface to them across the keyboard.

The MM57499 keyboard encoder, an NMOS silicon gate technology device, is designed to be a minimum 1C solution for the purpose of interfacing detached keyboards to terminals. It can reduce the usual 18 to 24-wire keyboard to terminal interconnection to a 5-wire connection. The 96-key operation is a simple direct interface to 12 X 8 matrix keyboard. The additional capability of a 114-key option can be obtained by implementing an inexpensive 4 to 12-line decoder 1C between the MM57499 and a 12 X 12 matrix keyboard. If fewer than 96 or 144 keys are used, no connection is required in the matrix at the unused key locations.

The Tatung 71739 keyboard uses short plate mounted cream Alps SKCC switches, not General Instrument Series S950 like in the Tatung Einstein TC01. The keyboard features a buzzer which is also marked as such on the PCB.