See if you can talk your local school district into buying a computer that costs about $5,000 and weighs 40 pounds. That was HP’s proposition to schools back in 1968 so really it is more like $35,000 today. The calculator had a CRT display for the RPN stack that you could mirror on a big screen. You could also get a printer or plotter add-on. Pretty hot stuff for the ’60s.
The 1970 videos promoting the HP 9100, posted by the [Computer History Archive Project], shows something we’d think of as a clunky calculator, although by the standards of the day it was a pretty good one with trig functions and a crude programming capability.
You could save your program on a magnetic card that looked more like a credit card than HP’s later magnetic cards for calculators. It also had an optical mark sense reader so students could program cards at home using a pencil, presumably running test programs or submitting homework answers.
Honestly, this seems hokey today, but back then this was pretty amazing stuff. Graphing calculators did take over the classroom, but not until the students could have their own for a bit more reasonable price.
Apparently, Bill Hewlett said that they would have called the 9100 a computer, but it would have confused their customers because it didn’t look like an IBM computer. Naming it a calculator cued customers that it was something different. The device had no integrated circuits and was similar enough architecturally to an Olivetti Programma 101, that HP was forced to pay about $900,000 in royalties to Olivetti.
If you watch the video to the end, you’ll see a 1970s-era physics instructor show how to use the 9100 to explain a body in motion. Not exactly a Zoom class, but pretty close for five decades ago. If you want to check out the slick marketing brochure for the machine, it lives as a PDF file. There’s even an example of plotting the frequency response of an LC network. You can even read some electronics and other types of programs for the beast in the HP Computer Museum.