NavList:

"I can’t be the only one left, as improved clones and free software simulators of some of their classic models are still being developed."

Hello, all... I have not contributed to the group in a very long time.  This peaked my interest.

I have a collection of over 30 HP calculators.  They are terrific.  Yes, HP does not make calculators much any more, but the emulators abound.  Check out:
- https://www.hpmuseum.org - a very nice resource full of software, emulators, photos, etc.
- http://www.pahhc.org - the PPC was an HP calculator club, that had a journal and had real power users that learned about the assembly language of many of the models, and their website contains so much stuff that the best thing to do is buy for $20 or so a USB drive that they will send you with about 15 GB of files
- https://thomasokken.com/free42/ - a website with a nice emulator called Free42 (like the HP-42S) for Mac//Win/FreeBSD and an iPhone app
- https://hp.giesselink.com/emu48.htm - my favorite HP-48/49 emulator that runs nicely on Mac/Win/FreeBSD

And speaking of early HP-35 users, William F. Buckley (the conservative from Connecticut) did a film ("Celestial Navigation Simplified with William F. Buckley, Jr.") and a book about using the HP-65 (the first card programmable HP calculator) for sight reduction.  Sadly his Wikipedia page does not yet mention this aspect of his life.  (https://en.wikipedia.org/wiki/William_F._Buckley_Jr.)

My life was changed with HP calculators.  I already had been reading Bowditch and was a bit overwhelmed by the math as a 10 year old, but when in 1975 I got my first HP-25C calculator, one of the first programs I put into it was a great circle triangle navigator solver.  It really helped me get to the next level in my pursuit of  understanding the process of celestial navigation.

Thank you Mr. Hewlett & Mr. Packard for your wonderful calculators!

Dan Allen
Idaho Falls, ID