Hewlett-Packard Calculator Emulators

[tbp1...@gmail.com]

Sometimes there is just no substitute for a good calculator.  Even though your computer could do a little calculation for you - if it had a decent calculator program - the applet that came with the OS is hopeless and you are stuck.  I sometimes use one to calculate parameters for use while I am working with GF4, and I have occasionally had other needs for a calculator in the past.

I am very fond of HP Reverse Polish Notation (RPN) calculators.  I used one or another professionally for years before -and sometimes after - the advent of practical personal computers.  If you aren't used to RPN, it takes a little getting used to, but it's generally much easier and faster to use once you have.  Those of you who have used them in the past know what I mean.

There are on-screen emulators for a number of HP calculators, and they work well (some of them may be for Windows only).  The best ones use the actual microcode extracted from old calculators.  HP had some engineers who really knew their stuff about arithmetic calculations and maintaining precision in difficult cases, and their algorithms were generally outstanding.

A number of these calculators could be programmed, a feature I made good use of. But the extra functionality makes the keyboard more complicated and hard to read.  Probably few of us will actually do any programming with these emulators even though they support it.

Some of the calculators that are available include the HP35 (the original HP pocket calculator), HP45, HP21, HP25, HP41, and HP15c.  I recommend the HP-45 emulator because it has the best combination of functions, simplicity, and an easy-to-read onscreen keyboard.  The HP-15c emulator is very good, but the calculator has a horizontal layout and is somewhat large, so it may not fit well on the screen with other program windows very well. It depends on your screen, of course. Here are some links for emulators -

HP 35, 45

HP21, 25

HP41

HP15c

Have fun!

[jkn]

I have an HP-35s calculator which I like but use fairly rarely - not enough to fully use the RPN features. It is a shame that battery life is relatively short.

At the age of 13 or so I first saw an HP-65 calculator not long after they came out, in 1974. My mum took me to some sort of education open evening and it was there on open display to play with, magnetic card reader and all. My teenage brain was never the same again...

[tbp1...@gmail.com]

There is a very good HP-35s simulator too, but I don't use it because, with all the programming and other extra features compared with the early HP calculators, it's too complicated to look at and use on a monitor.

The Reverse Polish Notation of my first HP calculator (the HP-45) prepared my brain to use FORTH, and that led to the basic design of the first ancestor of the GF4 Waveform Calculator.

With Windows 10 (I hope it will work on Windows 11, too), I've been doing simple arithmetic and unit conversions using the Start Menu type-in facility.  For example, tap the Windows key and type "21 deg c".  It shows you 69.8 deg F plus some other conversions.  Another one could be "5 oz in gr".  I never remember how big a hectare is, so: "1 acre in hectares" gives "1 Acre = 0.4047 Hectares".  "sqrt 640" gives the square root of 640.    It's really handy, and surprisingly flexible in grasping the questions (I imagine it's quietly going out to Bing to do the work).  More convenient than going through a search page in a browser, although search engines will do the same.

[Edward K. Ream]

On Fri, Aug 26, 2022 at 10:42 PM tbp1...@gmail.com <tbp1...@gmail.com> wrote:

Sometimes there is just no substitute for a good calculator. 

Thanks for the links.

Edward

[Thomas Passin]

Somehow I forgot to list the Free42, which is a re-implemented version of the HP-42.  Although the HP42 was programmable, the on-screen keyboard is not cluttered and is easier to read than most of the others.  Other good features: you can copy/paste the calculation results to/from the clipboard, and there are MacOS and Linux versions available.