Hewlett-Packard - Francis WEB

        
Hewlett-Packard was one of the reasons I started this collection. I worked for the company during 25 years, and my first month of work was spent in the repair center of the HP41C family. At that time, I was impressed by the technology and quality, but being a young engineer, I was more attracted by the mini-computers (HP85) or the large computers (HP3000 family).
My first calculator was an HP25, bought in 1978, and it cost me my 2 months of summer work. I still have it, and it still works.
Then I started buying more models, the HP41, the HP48, and this is how everything got started. I still consider the first HP calculators as one of the best built. There was a real sense of quality at that time, and you were expected to keep your calculator for a long time.

Note: I didn't add the Invent logo, I have a personal grief against Carly :-)

I Know that this list may not be complete, but this is already a very good overview of the models. I will simply list them by Alphabetic order.