Old Calculator Museum Advertising & Documentation Archive
Sharp Compet 20 (CS-20A)
Early advertisement for Sharp Compet 20 (CS-20A), Electronics Magazine, December, 1965
The Sharp Compet 20 was Sharp's second electronic calculator, utilizing
Silicon transistors versus the Germanium transistors used in their
first calculator, the
Silicon transistors were faster, more efficient, and much more
reliable than Germanium transistors. By the mid-1960's, Japanese
semiconductor manufacturers (NEC in this case) had perfected the
manufacture of Silicon-based transistors, making it possible for
Sharp to be able to build the Compet 20 using the technology and still
market it at a reasonable price.
The Compet 20 provides a capacity of fourteen digits (using
Nixie tubes for the display), with true credit
balance (negative number) handling capability. It is a four-function
machine with automatic floating and fixed decimal point modes. The
original sales price for the machine was around $1,050 in the US
at introduction in the fall of 1965.
To learn more about the Compet 20, see the Old Calculator Web Museum
exhibit: Sharp Compet 20.