Don took time to discuss with Karen the materials included with the donation so she could document how, where, and when it was used. We learned that in the late 1970’s this OSI would have been found in a chem lab at ICI (now Zeneca) in Wilmington. He described working with a colleague named “R. Earley” who wrote a BASIC program to calculate mole purity. From the looks of the code the output generated a graph plotting the slope relationship of a sample’s heat of fusion and the percentage of mole purity. I will post more technical details in a thread on vintagecomputer.net .

The computer may have been purchased in Newark, Delaware. There was an OSI shop on 92 East Main Street which is currently occupied by the Grain restaurant.

As far as the Challenger itself goes, I have it running well enough to boot up to an old Sony black and white television, via its “Sup-R-Mod” rf adapter. We may include this system in our upcoming 6502 microprocessor exhibit in the Spring.