Ohio Scientific Challenger 1P

Summary

Ohio Scientific (OSI) was founded in Hiram, Ohio, in 1975 by Mike and Charity Cheiky and Dale A. Dreisbach. It began building 6502-based Challenger computers in 1976. The Challenger 1P of 1978 is essentially a Superboard II single-board computer in a case with a power supply: a MOS 6502, 8 KB RAM, Microsoft BASIC in ROM, a cassette interface and a soldered-in keyboard. Expansion options provide 24 KB RAM and a floppy disk interface.

A revised version in a plastic case appeared in 1980. Larger members of the series include the Challenger 2P and the colour-graphics 4P.