A lambaste of mine had the first HP-45 on campus. Every electrical engineer just stared at it on his belt.
shows much of the old inventory. Reverse Polish notation; those were the days.
Make that lab mate. My apologies
When I started college in 1971 there was a big controversy over whether calculators should be allowed on exams. The argument was that it gave “well off” students an advantage over the slider rule. By 1976, it was no longer an issue, everybody had calculators.
For awhile I had a Sinclair that was also RPN. It was great until it started to make mistakes. After that I could not trust it and got rid of it.