Sharp EL-8: Difference between revisions

Sharp EL-8
Manufacturer	Sharp
Introduced	1970
Calculator
Display type	VFD
Display size	8 digits
Programming
Other
Serial Numbers	1012099

Revision as of 21:15, 15 July 2022

The Sharp EL-8 was an early handheld calculator produced by Sharp starting around December 1970.

Special features

Since the calculator uses the Itron font tubes it does not feature leading-zero supression, to help with readability (e.g. it would display '00000001' to display '1').

The calculator uses separate 'minus equals' and 'plus equals' keys, as well as a single key for multiplication and division, this was common for the time period.

Internal design

The calculator uses 3 PCBs internally, one for the logic, one for the display, and another for the power supply, the logic board and display board slot into a card-edge connector mounted to the keypad assembly, with the power board being connected to the display board via a wired connector and mounted with screws.

The calculator uses a reed-switch keypad, Vacuum Fluorescent Displays (8x Itron DG10L and 1x Itron SP8A), and 9 Integrated Circuits, the Rockwell AC2261, AU2271B, DC1152A, NRD2256, the Hitachi HD3121, and the NEC μPD190C.

Sharp EL-8

The Sharp EL-8 came in the colors black and white.

Gallery

Powered on.
Bottom case.
Badge (#1012099).
Rear of internals (with battery-bypass capacitor mod).
Front of the internals.
Powered-on without the display cage, there is copper tape against the back of the tubes and without the tape having a connection to ground the tubes will light dimly and unevenly.
Top of the keypad cage.
Bottom of the keypad cage.
Display board assembly.
Top of the logic board.
Bottom of the logic board.
Top of the power supply board.
Bottom of the power supply board (with battery-bypass capacitor mod).