HP-15c: Why so popular?

[rawi]

Peter Klein wrote:

Quote:I’m curious why the 15c is so popular.

I love that machine and in my case it is nostalgia and the effectivity with which I can use it.

My first HP calculator when being a student was a HP 33E, rather powerful, excellent manuals, really nice, but with just 49 programming steps and without constant memory...

My next one was the HP 34C. What an advantage! More programming space, more registers, constant memory and something no other handheld machine had: Solve- and integrate-functionality. It was so easy to use (e.g. exactness of integration just by setting the display format) and worked very reliable! No tables of statistical distribution needed any more! I used it heavily, perhaps too heavily. After about three years it was broken.

At that time I was no longer student but an assistant at a university chair for statistics. As a university employee I had access to a mainframe computer and as well to a PC. But I had to share these with many colleages, so access was limited. Furthermore there were no packages that could easily be used for integrating, for matrix computation etc. You had to write your own routines, by then in Fortran, to get the job done.

I replaced the broken HP 34C with a HP 15C. What a progress! So much registers! So much programming space! So much functionality! And it had again the solve and integrate functionality and additionally matrix functionality (complex numbers I did not need). There it was ahead even of the HP 41 family, which was much more expensive (at that time there was no advantage module yet). I had to prepare little exercises for students. All could be computed within seconds without going to a computer. I loved the display. Very easy to read, and energy saving, so there was no clumsy power supply needed. And the machine itself was very small and light-weighted. I used it heavily. Batteries were very long lasting. For me it was the feeling of having arrived at the ideal machine.

Yes, there was a learning curve. But there was an excellent manual as well, that helped a lot and was fun reading. Yes, the display information when programming was something you had to get used to. But after some weeks I knew that 43 32 meant g RTN. So in the daily usage those problems soon disappeared.

Perhaps nowadays many collectors can't understand how easy the handling got after some weeks of daily usage. If you switch all the time between different calculators of your collection you cannot get that familiarity I had (and still have after more than 30 years using other machines, because this one got broken as well after six years or so).

Best

Raimund