HP Calculator Museum

April 25, 2008 2:41 PM

Real nerds use HP calculators with RPN (Reverse Polish Notation)

You can read what happened to this endangered species here.

posted by Rafaelloello (74 comments total)

Right on! *hugs my HP-48GX*
posted by gyc at 2:47 PM on April 25, 2008 [1 favorite]

and I still can't believe that my dad gave away his HP-42S
posted by gyc at 2:48 PM on April 25, 2008

I learned how to extract square roots by hand, carried a slide rule (in my purse, not on a belt loop). I remember when in my first real job we bought the first calculator: it was a Casio, could only do basic arithmetic, did not have memory, and cost $528.

Those were the days!
posted by francesca too at 2:58 PM on April 25, 2008

My old-style, silver-logo HP41C still works. So does eV41, on my phone. hp41.org has a bunch of emulators on the 'Emulation' page.

Anyone else have a PPC ROM?
posted by jet_silver at 2:59 PM on April 25, 2008

I don't think so, posers.

Real Nerds rock the slide rule.
posted by MrGuilt at 3:17 PM on April 25, 2008 [2 favorites]

I recently bought a second HP-12C to keep at home. I just couldn't relax while my only RPN calculator stayed back at the office.
posted by mullacc at 3:18 PM on April 25, 2008

I still use my HP-11C on an almost daily basis.
posted by cairnish at 3:20 PM on April 25, 2008

defun truth ( n x y z )
( + x n z y )
(setf a "is the reason")
(setf b "Reverse Polish Notation")
(setf c "can be coded in strings, thus making it so goddamned useful")
(setf d "Common Lisp")
truth ( a b c d )
posted by Viomeda at 3:26 PM on April 25, 2008 [3 favorites]

HPCalc.org is also still being maintained as a repository of new and updated software for the 48/49/50 series.

I had a 48G until I accidentally stepped on it, but I replaced it with a GX. I desperately wanted a memory card so I could install the MetaKernel, which eventually became the basis for the OS in the 49 series. Sadly, back in 1999 a 128KB RAM Card was prohibitively expensive.

Viomeda: Lisp doesn't use Reverse Polish Notation but rather regular Polish Notation. The HP 48/49/50 series include a Lisp variant called Reverse Polish Lisp that uses RPN.
posted by jedicus at 3:31 PM on April 25, 2008

My dad worked for HP and would bring home all sorts of calculators for us to play with. I don't have any of them, but my dad still has his stainless steel HP01 calculator wristwatch.
posted by oneirodynia at 3:35 PM on April 25, 2008

Damn the batteries that corroded within my HP-48GX. Oh how I miss that calculator.
posted by whimsicalnymph at 3:35 PM on April 25, 2008

Amateurs.
posted by dersins at 3:43 PM on April 25, 2008

I recently picked up their retro-look commemorative HP-35S and *love* it. I got it specifical to learn and get used to RPN.
posted by mrbill at 3:48 PM on April 25, 2008

I got a 12C (financial rpn) for Christmas, and now I've gotta figure out how the heck to use the thing. Mainly I wanted it for the intimidation factor when I go in for large loans (house, car, etc...). Nothing like being able to call BS on their numbers immediatly.
posted by cschneid at 3:58 PM on April 25, 2008

There's a HP-48 emulator for the iPhone. It makes me happy.
posted by blahblahblah at 4:03 PM on April 25, 2008

I got an HP-34C for my tenth birthday and I was in heaven.
posted by Slothrup at 4:04 PM on April 25, 2008

I still miss my 15C. I have a 42S and a 48GX. The 42S is pretty nice, but the 15C is in my mind the archetypal calculator. I have fond memories of programming it to generate random integers to play D&D in 7th grade.
posted by pombe at 4:06 PM on April 25, 2008

My HP-28S still has it's place on my desk, though these days I tend to reach for my PocketPC running Math Tablet... In RPN mode.
posted by benzo8 at 4:18 PM on April 25, 2008

my dad worked for hp and one time i went on a factory tour where they had some robots doing some kind of assembly. each robot thingy was controlled by an hp calculator. i thought that was really cool. now i find it hard to even believe.
posted by snofoam at 4:38 PM on April 25, 2008

Growing up when it was not quite so shocking to tell "Pollack jokes", it blew my mind when my dad's friend pulled out this calculator that was backward and confusing and called it "reverse Polish" without a hint of irony.
posted by mkultra at 4:39 PM on April 25, 2008 [1 favorite]

I sold my 48Gand my 48GX when I abandoned Chemical Eng. (after switching from Electronic Eng.) in favor of Design School. One of the stupidest decisions I've ever made.

I even got a free color TI92, and gave it back in favor of the monochrome 48GX. Apart from the beauty that is RPN, no other calculator in the universe can match the solid feel and the tactile feedback from an HP calculator. I am sure someone could crack a coconut using a TI, but the calculator would be ruined. With a 48 series, you can crack open the coconut, use as a lure for a Stegosaurus, and brain it. You can then do some Celcius to Farenheit conversions and cook the lizard.

Anyone here willing to donate me a 48Gx? Please?
posted by Dr. Curare at 4:46 PM on April 25, 2008 [1 favorite]

My first was an HP-21, received for Christmas 1975. Begged my parents for it (junior in high school at the time), but it was $25 over my $100 budget for Christmas present requests. Thankfully it went on sale for $99 about 3 weeks before Christmas. Ah, the memories of waging war with my RPN over the dweebs with the TI SR50's and SR50As and their 37 levels of parentheses or whatever. To add insult to injury, I would effortlessly convert polar to cartesian coordinates in but a few tactiley-fed-back button presses.

I still can't quite figure out why the beautiful simulated brown leather case adorning my hip didn't net me more hot any chicks.
posted by Rafaelloello at 4:46 PM on April 25, 2008

I still use my 15C (almost) daily - got the thing back in 1984, and it's survived being dropped countless times. The tactile feedback can't be beat.
posted by needled at 5:00 PM on April 25, 2008

I still regret trading my 48g for a TI92. I finally got rid of this toy and got a new HP 33S.
posted by racingjs at 5:05 PM on April 25, 2008

RPN is to TI-eighty-whatever as stick is to automatic transmission. You feel closer to the machine.
posted by proj08 at 5:15 PM on April 25, 2008

32sII user here. Have a 49G, but it's got a nasty keyboard.

My dad's an ex-HP salesman. He's had his HP11C since they came out. The great advantage of an HP is that no-one will "borrow" it, since they can't get it to work. He also noted that, on fitting the third set of batteries a couple of years back, that that set of batteries would likely outlive him.
posted by scruss at 5:27 PM on April 25, 2008

Don't they make things like matlab, maple, or mathimatica for PDAs now? What's the point of a dedicated calculator?

Plus, TI's all the way.
posted by delmoi at 6:00 PM on April 25, 2008 [1 favorite]

The great advantage of an HP is that no-one will "borrow" it, since they can't get it to work.

6 X 47... "Hey, where's the "equals" button?"
posted by Rafaelloello at 6:06 PM on April 25, 2008

My current calculator is an HP-16C. Same batteries since 1987 (to the youngins: these aren't rechargeables either).
posted by Rafaelloello at 6:11 PM on April 25, 2008

I still have an HP (47?) in my desk drawer. But I also have a linux machine, and:

xcalc -rpn &

works just fine.
posted by Ella Fynoe at 6:13 PM on April 25, 2008

So two days ago I was starting a statistics final. One of my fellow students quietly asked the professor if he had a calculator he could borrow. The professor said sure, it's just down in my offi—and then he stopped short and uttered these beautiful words:

"Oh! Did you need a calculator with an equals sign?"

I gave my 48G a long, affectionate look.

And then, of course, proceeded to snap through several calculations in the order I found mentally convenient, rather than that dictated by written notation. Prof did come up with a "normal" calculator eventually.
posted by eritain at 6:22 PM on April 25, 2008

/me makes mental note to explore the predictive relationships among RPN use, stick shift, and Dvorak keyboards. proj08 speaks truth, and so does scruss. delmoi, on the other hand, trolls.
posted by eritain at 6:25 PM on April 25, 2008

I tried RPN, but found it sucked to think differently on my calculator than I did in Excel. Plus, the TIs have, you know, parens. And even though a stick "feels" closer to the car, only Schumi actually is going to outperform the box. (As I sadly learned with my stickshift.) And Dvorak isn't any faster, so stop showing off, eritain.

*runs*
posted by sachinag at 6:34 PM on April 25, 2008

I still use the HP48G I got for AP calculus in grade 11 just about every day. I dread the day when it breaks. Any calculator running on a computer or PDA, even if it's RPN or emulates the HP, just doesn't feel the same.

dvorak and stick shift here too
posted by Emanuel at 6:39 PM on April 25, 2008

My dad had one of these old Reverse Polish Notation HP calculators with a lot of sentimental value. Now I understand why he was really disappointed that when I took AP Calc I was required to buy a Texas Instruments calculator and there wasn't any kind of HP that I could get.
posted by Tesseractive at 6:44 PM on April 25, 2008

Real nerds use programming languages with Reverse Polish Notation.
posted by Slithy_Tove at 6:55 PM on April 25, 2008

I still have my HP16C from grad school !! I needed it for my Compiler Design class, as well as for some of my IBM Systems 360 Assembler classes. Goodness, that was so.long.ago.

I included it in one of my sillier flickr shots many years ago.

And you know, it still works!
posted by seawallrunner at 7:34 PM on April 25, 2008

Keep you iphones handy folks, if HP stops making their calculators you can always grab the apps off Installer.
posted by mullingitover at 7:35 PM on April 25, 2008

This is news, how?

I used to be bilingual-- I could use classmates' HPs as well as my Sharp. My dad was an engineer, but he was a slip-stick guy, and the company got all the design engineers non-HP calculators when they gave up slide rules, so he never really understood the allure of HPs.

Now I don't need a calculator that does more than the freebie I got in a package of RayOVac batteries....
stick and qwerty (but I share the computer with my kids, so....)
posted by jlkr at 8:09 PM on April 25, 2008

I love RPN
posted by davebarnes at 8:13 PM on April 25, 2008

My first calculator was a Bowmar MX120. It died on me two weeks before finals one year. My dad took advantage of my empty pockets and offered to buy me an HP-25 if I shaved off my beard. I don't know if it was the bare chin or my insistence on showing how I could program my new calculator to count, but my girlfriend left me soon after.
posted by forrest at 8:26 PM on April 25, 2008

Rafaelloello :

My first calculator was also an HP-21, which my parents bought me as a high school graduation present, also in 1975. I later moved up to a 29C, then after that the programmers model (12C ? I can't remember exactly).
posted by rfs at 8:37 PM on April 25, 2008

Just out of curiosity - would there be something wrong with getting a new HP 50g? Is the magic dead?
posted by facetious at 8:40 PM on April 25, 2008

I lost a 48GX (technically a friend's) when my backpack got stolen. Damn thief probably didn't even know what it was he got.

Once I learned to use RPN, it become hard to use regular calculators. I still tend to think math that way.
posted by JHarris at 9:14 PM on April 25, 2008

I didn't want to fool with RPN so I bought the 17B instead of the 12C. No nerd cred for me!
posted by Daddy-O at 9:31 PM on April 25, 2008

facetious: In my opinion, the redesign sucks. It is like the equivalent of web 2.0 redesigns of classic web sites. If you can, hold a 48 and a 50 in your hand, click a few buttons, and feel the difference.
posted by Dr. Curare at 9:33 PM on April 25, 2008

Calculator.app in OS X also does RPN (look under the View menu for the RPN option).
posted by mrbill at 9:36 PM on April 25, 2008 [1 favorite]

I recently discovered that the calculator app on the mac will do RPN and show the stack. Happy day! I have a hell of a time using a hand-held calculator that requires me to use paren buttons. RPN just makes so much sense.
posted by ctmf at 9:36 PM on April 25, 2008 [1 favorite]

By the way, does anyone still have the book of games you could progam into the 41C? I spent many an hour of long car trips playing Hunt the Wumpus and Moon Lander.
posted by ctmf at 9:39 PM on April 25, 2008

what are the odds that ctmf and I would BOTH post about OSX's Calculator.app doing RPN, at the EXACT SAME TIME?

Use your calculator to figure it out.
posted by mrbill at 9:59 PM on April 25, 2008

My 41C battery contacts are corroded. :( I left the batteries in too long.

Anyone know how to clean off the copper contacts? Some of the corrosion is pretty bad. Very, very sad. That was the best calculator I ever owned. I think I bought it in 1979.
posted by e40 at 10:12 PM on April 25, 2008

Calculator porn, my favourite. I love my 48G. I am still sad that I didn't buy an 32sii when I had the chance (to work around the 'no programmable calculators during exams rule'), and fondly remember finding a HP-19C (yes, w/ extra paper rolls, and many manuals) in a waste pile, while roaming around waiting for students during office hours. Pure joy.

facetious: no, the feel of the buttons is different, and the interface has changed, a poor facsimile of the glory days
posted by rider at 10:20 PM on April 25, 2008

GRPN. I like it because my hands never need to leave the main keyboard. I have several slide rules, also :-).
posted by Araucaria at 10:35 PM on April 25, 2008

I loved my 48GX. It was the best calculator HP ever made, or will make.
posted by ryanrs at 11:26 PM on April 25, 2008

I tried RPN, but found it sucked to think differently on my calculator than I did in Excel. Plus, the TIs have, you know, parens.

Bah. Neither toy is fit for computation.
posted by ryanrs at 11:35 PM on April 25, 2008

jedicus - I've always thought of RPL less as a variant of lisp than as the bastard child of lisp and forth...
posted by russm at 12:41 AM on April 26, 2008

BTW, it's called "Reverse Polish Notation" because Jan Łukasiewicz Notation defies pronunciation. (also typing)
posted by ryanrs at 12:53 AM on April 26, 2008

I've been in love with RPN ever since I got my own HP calculator. You'll have to pry my 48G+ from my cold, dead hands.
posted by splice at 1:23 AM on April 26, 2008

I'm in love with rpn too.
posted by rpn at 5:21 AM on April 26, 2008

(btw, my username doesn't come from reverse polish notation (see my real name for a clue instead) :))
posted by rpn at 5:22 AM on April 26, 2008

Well, I have the 50G. At least I got a decent deal on it, and I was using a TI-82 before that. Bleh.

I don't use the RPN mode on it, though. I keep meaning to start using it, but right now I really don't have the luxury of shifting my world view so close to my Calculus final.

I used to drive a stick, and I wish I still did, but the car I recently bought is an automatic. Got a deal on that, too, heh.

Standard QWERTY for me too. I did teach myself how to touch-type when I was a kid, I just used what was available.
posted by Talanvor at 6:18 AM on April 26, 2008

Okay, would you nerds quit wanking over RPN and explain to me (an undergrad ecology major, who grew up loving his TI83) what all the fuss is about?
posted by lostburner at 9:13 AM on April 26, 2008

W00T! RPN!

I still replace the windows calc with a freeware rpn calc, cuz I can never remember how to do math without a stack.

My HP-33E cost $180, and I paid it myself over about half a year when I was 12. But it was programmable to the tune of 49 machine language steps. I miss lunar lander, where all you get is a velocity and a height to the left and right of the decimal point, respectively.
posted by lothar at 9:14 AM on April 26, 2008

lostburner: "Okay, would you nerds quit wanking over RPN and explain to me [...] what all the fuss is about?"

lothar: "W00T! RPN! I still replace the windows calc with a freeware rpn calc ..."

HEY!
posted by lostburner at 9:33 AM on April 26, 2008

My 10C is sitting right here in front of me. Use it every day. I love giving it to people when they ask for a calculator. ... you know, my dad loved doing that too... When they can't figure it out, I tell them "Oh, it's reverse polish". That never really seems to help them at all.


;-P
posted by humboldt32 at 9:59 AM on April 26, 2008

Free graphing calculator download, with come interesting features.
posted by Brian B. at 10:00 AM on April 26, 2008

Before seeing this, I would honestly have assumed anyone referring to a "desktop calculator" was joking.
posted by Mr. Anthropomorphism at 10:45 AM on April 26, 2008

lostburner: RPN calculators remember numbers in the stack and do calculations on them.
Example: 270 ( 5 + 3 )
You type: 270 (enter) Shows: 270
You type 5 (enter) Shows: 5
You type 3 + Shows: 8
You type * Shows 2160, the answer.

It's not that much different for simple problems, but for big ones with nested parens, it's much simpler to start at the beginning and just type right through.

When I use a TI or something, the first things I usually get stuck on are the y^x button and the % button. How those work seem to vary from calculator to calculator. With RPN, it's obvious how they should work and they do it immediately. I suppose that wouldn't matter so much if I had one type of calculator I used all the time. At work, we just have a bunch of random ones lying around, and you pick up the closest one when you need it. Then spend a few minutes trying to figure out what the range of .576 +/- 25% is (for example). Drives me nuts.
posted by ctmf at 11:18 AM on April 26, 2008

Mr. A: why not? Why would you sit there typing a report in word or something, then say ah, crap, what's this value, open a drawer - crap, not in there. Open another drawer, nope. Who stole my calculator? Try to do it by hand. Is that right? do it again to check, etc.

When you have a big expensive calculator under your fingertips? cmd-(space) "cal" (enter). Bam. Instant calculator.
posted by ctmf at 11:26 AM on April 26, 2008

How I miss the glowing LEDs of my 34C (the manual for which showed how to program a lunar lander game). But at least I can still use RPN on my 32SII (even though the LCD display is boring)
posted by jasper411 at 1:03 PM on April 26, 2008

lostburner: RPN calculators remember numbers in the stack and do calculations on them.
Example: 270 ( 5 + 3 )
You type: 270 (enter) Shows: 270
You type 5 (enter) Shows: 5
You type 3 + Shows: 8
You type * Shows 2160, the answer.


Or stated a different way, you use the calculator exactly like you would do the problem on paper. It's always number, function, number, function, etc.

Of course you often need two numbers before you can do anything, so the enter key merely separates one number from the other. In the above example on paper your would write down the 5, write down the 3, then sum them, then you write down the 270 then multiply.

5, enter, 3, + (now you have the intermediate result, 8)
270, x (now you have the final result, 2160)

9 key presses and you're shown the intermediate results along the way.

Once you can visualize the stack(not covered here), there is much greater power to be unleashed, but it's not necessary. My wife borrows my HP-16C all the time to do basic calculations and doesn't have a clue about the stack. She just knows it's number, enter, number, function to get started.

Of course she does have a little trouble if I leave it in Hex mode.
posted by Rafaelloello at 1:28 PM on April 26, 2008

ctmf: I meant I truly did not know there was ever a desktop-sized device that only functioned as a calculator. Had someone mentioned such at thing, I would have assumed it was a brusque metaphor for a Windows 98 machine, or something to that effect.

I'll get off your lawn now...
posted by Mr. Anthropomorphism at 7:11 PM on April 26, 2008

cmd-(space) "cal" (enter). Bam. Instant calculator.

Or if you have Leopard, Command-Space, start typing your sum.
posted by cillit bang at 12:13 AM on April 27, 2008

Holy crap you guys are nerds.

'course, without nerds, we wouldn't have an internets. All hail the nerds!
posted by dirtynumbangelboy at 2:43 AM on April 27, 2008