Additional Pictures 


This Concept 24 Version 3 was manufactured in 1976 
by an unknown company in Hong Kong.

The printed circuit board (PCB) of the CONCEPT 24 Version 3
hides the name of its manufacturer.

The keyboard assembly of the CONCEPT 24 Version 3
lists a company called ETCO but no further information.

The main electronics of the CONCEPT 24 Version 3 calculator
is centered around a Rockwell A5901CA Integrated Circuit.

The A5901CA single-chip calculator circuit.

horizontal rule

If you have additions to the above article please email:

Joerg Woerner, February 5, 2010. No reprints without written permission.