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How I love my HP-16C

A while ago I bought an HP-16C calculator on eBay. It wasn't cheap and there was no manual; the calculator itself works fine and is in almost mint condition. Since then I've fallen in love with the device.



You probably think I'm nuts to be using a calculator that was discontinued in 1989 and only 203 bytes of memory. And I had to pay extra to get a PDF version of the scanned original manual.

Perhaps I am crazy, but here's why I love this little machine:

1. RPN. You either love this or hate it. This is my first RPN calculator and for me RPN is the right way to use a calculator. I read a short introduction to RPN tricks (of which there are very few, but filling the stack for repeated operations is one and using LST x to prevent the stack from moving is another).

2. The industrial design of HP calculators is pure art. They are the right size for your hand, the keyboard is clearly marked, keys are spaced far apart (which avoids fat fingers like mine) and the keys give good feedback on being pressed. And the calculator is slightly slanted so that when it's on the desk it's easy to type on.

3. Floating point with fixed display of decimal places. Just right for balancing your check book.

4. Hex/Dec/Oct/Bin modes plus the nice 'show' feature which can display a number in one of the other bases for a few seconds without changing base. Very handy when debugging.

5. And my favorite thing... the HP 16C is 128 mm wide and 79 mm deep. Notice anything interesting? 128 ENTER 79 / is... 1.62. Or the Golden Ratio. No wonder I love that thing so much.

Comments

Anonymous said…
I have BOTH a 16C and 15C which I bought way back in senior school. Would NEVER give them up. They're simply the most rugged and best devices ever made by HP. Shame the newer models have skimped on the ruggedness.

A buddy of mine during university saw an 18 (or a 16) wheeler truck run over something that looked like a HP 15C that must have fallen from a student's bag. The thing STILL worked! The only damage was a cracked LCD. He took it to an HP shop and asked to have it repaired, instead they offered him a new one in exchange for the old one they wanted for sales demonstrations!
Anonymous said…
i use to have a 16C. the only grip
i had was the floating point was
not ANSI, I at the time was doing
a lot of FP <-> HEX/binary conversions.

-pete

PS and a lot of PDP/11 FP <-> Octal :)
Anonymous said…
I went to lengths for one several years ago. The only place I could find one was Ireland - I live in the US. Shipping was a bit expensive, but it was worth it!
Anonymous said…
There are several nice HP16 emulators, except for some that you have to use the mouse, not keys. Ick.
Not the same as metal in your hand though.
sch said…
I have one going on eBay. No manual and it has some of my school info scratched into the back (not over any of the diagrams though). Rest of the calculator is MINT and it works great (was stored without batteries, I just put 3 new ones in last week). Check it out at http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=140286888523
webmasterpdx said…
I bought an HP16C in the 80's and they were invaluable for anyone working close to the hardware. As for standard Floating point, I had to use several different formats of floating point and I wrote programs to convert back and forth to integers....was very useful as a programmers calculator and would still be. I have to find a replacement LCD as mine is broken. Everything else works....
michael said…
I have two HP 16C, simply the best programmers calculator ever produced. I bought mine when I left university, 30 years ago. I still use them every day as I still do low level programming. Who would have thought something designed 30 years ago would have a programmable bit size up to 64 bits and good old Intel/MS/Linux are just getting there with 64 bit operating systems. You can even get a 128 bit multiplication result.
This calculator is the dogs bollocks bar none.!!!
michael said…
I have two HP 16C, simply the best programmers calculator ever produced. I bought mine when I left university, 30 years ago. I still use them every day as I still do low level programming. Who would have thought something designed 30 years ago would have a programmable bit size up to 64 bits and good old Intel/MS/Linux are just getting there with 64 bit operating systems. You can even get a 128 bit multiplication result.
This calculator is the dogs bollocks bar none.!!!
Dean said…
I have an original HP 16-C since the '80's, I'm a programmer and still use this calculator almost daily - still working great!
dgourlay said…
Not sure if this blog is still active, however I thought it may be worth a shot:

I recently created a petition to bring back the HP 16c http://www.change.org/petitions/hewlett-packard-development-company-bring-back-the-hp-16c

The 15c was reproduced as a limited edition. Let's do the same for the 16c!
World Traveller said…
Swiss Micros (swissmicros.com) make a replica of the 15C and 16C: I have both. Physically, they are the same size (129mm x 76mm), the only difference being a MicroUSB connector so you can connect it to your laptop etc. Functionally, they appear to be identical to the originals. Cost 119CHF each - very happy punter!
World Traveller said…
Swiss Micros (swissmicros.com) produce replicas of a number of HP machines. I have both their 15C and 16C replicas. Physically, they are the same size as the originals (129mm x 76mm), slopped case etc, but also include a microUSB port for connecting to a laptop. Functionally, they appear to be identical to the originals. They cost 119CHF each in April 2018, with prompt delivery.

Very happy punter!

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