8 ms·

The early history of HP calculators

93 points by ohjeez 9y ago

gaius 9y ago
Still got and use my 12C, and 48gx, unfortunately sold my 28 to buy the latter. When you look at the quality of what HP used to produce versus now, it's very sad.
- b5 9y ago
  I have a couple of 12Cs -- one made the year I was born, and the other made 2011 -- and an 11C. I use my 12C for absolutely everything, and couldn't live without it. The one made the same year I was born (1983) is a sturdier, but the 2011-made one is also excellent. I also had a 48GX but sold it -- I didn't use it, and I preferred the more compact Voyager series, even if the stack isn't displayed on screen. I agree that the build quality has dropped over time, but I'd still choose an RPN HP over anything else.
- agumonkey 9y ago
  Yeah they decided it wasn't worth their time, probably because the market shrunk. They could have made money on the education market because their RPN is a wonderful thing but it would require to explain things to kids and teachers .. so now it's all built by another company. I sniped a 48SX on a Craigslist equivalent for 20$, the guy even sold the full manual and 3 math/asm books, I couldn't resist. I'm learning electronics, I plan to mod it if I can, maybe an ESP8266 "coprocessor", a rechargeable lithium bat. and a usb port.
- mschaef 9y ago
  > When you look at the quality of what HP used to produce versus now I was always impressed that the keys used two color injection molding for the primary labels. There was almost literally no way to wear the label off the keys, since the label was built into the plastic.
jimnotgym 9y ago
I'm too young to remember, but it seems the UK calculator of choice was the Sinclair http://www.vintagecalculators.com/html/sinclair1.html http://www.vintagecalculators.com/html/sinclair1.html
- b5 9y ago
  My dad, who went to Uni in the '70s to do maths and physics, has a Sinclair scientific that looks very similar except has blue LED digits. I don't know the exact model.
  - nothotdog 9y ago
    the bright blue LED had not been invented yet, it was probably vacuum flourescent http://www.vintagecalculators.com/html/calculator_displays.html http://www.vintagecalculators.com/html/calculator_displays.h... https://en.wikipedia.org/wiki/Light-emitting_diode#Blue_LED https://en.wikipedia.org/wiki/Light-emitting_diode#Blue_LED
- Theodores 9y ago
  This article is much like the US rather than the UK history where we had a separate, home grown path. I think I am the last generation to have a legendary calculator in the Casio FX 82A. Nowadays computers have taken over.
userbinator 9y ago
Notice the distinct lack of an '=' button --- HP's calculators have been almost exclusively RPN-based. It's funny to watch other (newer) developers reactions when they ask to borrow the calculator that's usually on my desk (a 42S) and then give it back several minutes later, with a puzzled look on their faces.
- b5 9y ago
  At my last job, which involved a lot of number work, my boss would often pick up my HP-12C to quickly calculate something we were talking about. Every single time, he'd say, "Your calculator is broken," then put it back on my desk. It became a running joke of ours.
- ece 9y ago
  A 42S that a high school friend had was how I first learned about RPN and HP calculators. Bought a 48G soon after which I still have. I use the prime app on android now which works well when needed.
- agumonkey 9y ago
  "you've been stacked" -- HP calc owner Last year I finally read the whole manual (as a teen I only used the symbolic differentiator, most useful and magical to my brain at the time). Since I learned about Lisp, so RPN programming features appealed to me. I realized that: 1) RPN has lambda << 2 + >> means (lambda (...) (+ 2 ...)) 2) RPN has a short syntax for them << a -> a 2 + >> Yes, 1990 HP RPN had arrow notation out of the box. Take that ES6 !
  - nemoniac 9y ago
    If you're enjoying that, you'll find even more connections with Forth, also a very cool programming language. https://en.wikipedia.org/wiki/Forth_(programming_language) https://en.wikipedia.org/wiki/Forth_(programming_language)
    - agumonkey 9y ago
      I love stack languages. Forth, Factor, Joy, Cat .. (all the concatenative crew). ps: there are some Chuck Moore talks on youtube that are worth gold. His CPUs are heaven
KGIII 9y ago
I am pretty old. The first computer I touched was an HP. They called it a calculator, my understanding is that this decision was based on the fears people had of computers back then. Hmm... I don't recall if it was the A or B. But, here is a video that is more than you wanted to know: https://m.youtube.com/watch?v=JmTyrS-jfi0 https://m.youtube.com/watch?v=JmTyrS-jfi0 If you're curious, I hated it. In retrospect, it was pretty awesome. At the time, I hated it. I basically hated computers up until the mid-90s. I didn't really like them for another ten years. Now, the relationship is like that of old adversaries that are too tired to fight any longer.
pmoriarty 9y ago
I've never used an HP calculator, but I've recently been getting interested in emacs' calc, which is also RPN. Could someone who's used both talk a bit about how they compare? Are calc and emacs missing something that made HP great?
- agumonkey 9y ago
  Single hand operation and wonderful click feel of HP calc buttons (before the 49 model of course) ;)
- acomjean 9y ago
  dc on the unix command line (linux too), is an rpn calculator. I use its non rpn counterpart bc. I've been told they aren't great (buggy), but for simple math they work fine. I used a hp 32S in college, less mistakes make with rpn then entering calculations the other way. though newer calculator allow entering of whole equations ((10 *5)^2)/3 made this less useful. The hand helds are more portable than emacs.
- tyingq 9y ago
  You can try an HP48 here: http://www.poleyland.com/hp48/index.html http://www.poleyland.com/hp48/index.html
- mschaef 9y ago
  Interesting you ask.... Emacs Calc was inspired by the HP-28. https://www.gnu.org/software/emacs/manual/html_mono/calc.html https://www.gnu.org/software/emacs/manual/html_mono/calc.htm... It's not the same, but having used both, they are very similar in overall feel. > Are calc and emacs missing something that made HP great? A couple things: First, having specific hardware is (was?) a nice thing. Secondly, the HP28/48 programming model was very, very orthogonal. It was a more impoverished Lisp than even elisp is today, but it pervaded the entire software stack. While people referred to 'RPL' and 'System RPL' with two different names, the truth is that there was no real distinction between the programming language you used as a user and the programming language used by HP to build the machine in the first place. This kind of solidity and general 'gestalt' pervaded the operation of the machine and made them joys to use.
jaclaz 9y ago
Probably I will sound like a dinosaur, but I actually remember a time where the HP-97 was a daily used tool at work. 256 steps of program! I could write small programs that calculated coordinates for road topography, circular curves and even (with a very little approximation) clothoids. And you will have to pry out from my cold, dead hands my HP 28C[0][1], I bought it right when it came out in 1987 (yes, that is exactly 30 years ago) and it still goes strong. But to give you a data point, I payed for it (in 1987) around 650,000 Lire, something like the equivalent to 330 Euro that nowadays would be roughly 750 Euro. [0] https://en.wikipedia.org/wiki/HP-28_series https://en.wikipedia.org/wiki/HP-28_series [1] http://www.hpmuseum.org/hp28c.htm http://www.hpmuseum.org/hp28c.htm
tzs 9y ago
I never personally saw this, but I've been told by people that the HP-41 could be massively overclocked at the cost of heavy loss of battery life. Supposedly they could be overclocked sufficiently to handily beat common minicomputers, such as the PDP-11, at floating point. Allegedly some people hacked interfaces between their PDP-11 and their overclocked HP-41 that allowed the PDP-11 to use the calculator as a floating point coprocessor.
- hota_mazi 9y ago
  Correct. The HP 41 had something called "synthetic programming", a flaw that someone once found in the calculator that allowed access to a lot of its internals, including brand new opcodes and capabilities (even graphics, which the HP 41 didn't officially support). The downside was that doing the wrong thing could cause the calculator to shut down sometimes for days in a row. I once did that to my father's calculator and these were the longest days in my life, dreading that I might have broken his $300+ purchase for silly programming antics.
dm319 9y ago
Getting good condition HP calculators can be quite expensive second hand. People interested in buying a new one should check out swissmicros [1]. They are bringing out an HP42s clone with quad precision decimal accuracy, which I'm looking forward to! [2] [1] http://www.swissmicros.com/ http://www.swissmicros.com/ [2] https://www.youtube.com/watch?v=8LatjXPgLI8 https://www.youtube.com/watch?v=8LatjXPgLI8 EDIT: I don't have any involvement with swissmicros apart from anticipating their new calculator
- zokier 9y ago
  One thing that has always befuddled me with HP calcs is their model numbers that don't seem to follow any rhyme or reason. How does the functionality of DM42 compare to for example WP34? And how does -48 compare, besides the relatively useless graphing capability? I see lots of people also preferring some other models (15, 16, 35, 41 etc), which I would have imagined to be strict subsets of these "juggernauts", but maybe that is not the case?
  - brians 9y ago
    The 48s show you four rows of stack at a time, and can use that to show a single long expression. That can be a huge difference—though of course, unlike the time when these were built, we have Octave and similar right there.
    - zokier 9y ago
      DM-42 seems to also feature multiline display (I'm kinda assuming that it will be showing the stack?), so that advantage is mostly negated there?
  - dm319 9y ago
    The 48 was quite a bit bigger than the 42s, which I think is the main downside. A bit of googling suggests the 48 contains similar features to the 42s, and probably more. It can also show the full 4 level stack - the 42s showed 2. However, you're looking for the best all-round scientific calculator (form factor restricted!) the 42s probably wins. The voyager series (including the 15 and 16) were well-made and in landscape format, which is nice for using on-the-go with both thumbs. They are more simplistic though - you see one line of the stack, and there aren't menus - hence several variations to cater for different markets. The HP41 was an impressive programmable calculator for its time, and seems to be more expandable than the 42s. However, the 42s is programmable, has a few more features and a more modern display. Not sure about the WP34, though if you look at the cost of a second hand 42s, you'll see that many people rate it much higher than more modern HP calculators. I think what puts me off more recent calculators and even some other HPs, is the ambivalence about RPN. I really like RPN, and don't like when the UI is compromised to please both. [1] http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv005.cgi?read=9278 http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv005.cg...
protomyth 9y ago
I miss the HP-16C. It was an amazing thing to have something with hex. It was pretty useful when I was doing assembly.
- paraplegic 9y ago
  A GREAT calculator. I wrote a portable forth which I use for hex conversion which I still use frequently.
wslh 9y ago
I just bought a new HP 12C to replace the calculator app. I love the form factor, mainly the keyboard, but they could improve the product adding more memory for programming. It is odd they have an emulator in place to run the original ROM! BTW I have also a HP 48GX but some buttons become unusable. What is the best shop to repair it?
noonespecial 9y ago
I'm a young-un in the HP world. 48g was my first and still only. But you can pry it from my cold dead hand because the snap of those lovely keys under your fingers and that stack scrolling up that screen is the visceral feeling of math.
siberianbear 9y ago
Wow, this is bringing up some memories of my childhood. One of my childhood friends had a father who was a licensed surveyor and civil engineer. He showed me how to write programs one one of these calculators. I was fascinated with it, and started writing simple programs to do obscure calculations. After I showed him what I had figured out, he showed me how to remove the faceplate and access a special test mode by pushing some hidden buttons near the . key at the bottom. In retrospect, I can't figure out how some civil engineer in a rural area knew how to access and use these test functions. Probably, he had a friend from the university who worked at HP or something. I remember that these calculators use something called RPN (Reverse Polish Notation). To do "3+4" you enter 3 <enter> 4 <enter> + <enter>. I had a university professor ask once, what's the opposite of RPN: when you enter "+ 3 4"? One other student answered "Reverse Italian notation?" And everyone in the class laughed so hard...
- MegaDeKay 9y ago
  Actually, to do "3+4" you enter 3 <enter> 4 + That's it. Note that this is one keystroke less than the regular calculators used by mere mortals, and that is why RPN rules. Source: my daily driver HP-15C that I've had since around 1985. Works perfectly and has only gone through two or three sets of batteries. I'd swear it was solar powered.
  - ZenoArrow 9y ago
    Isn't that the same number of keystrokes? [3] [+] [4] [=] [3] [Enter] [4] [+] Both use four keystrokes.
    - jaclaz 9y ago
      Yes, bad example. See here: http://calculatorauthority.com/why-use-a-reverse-polish-notation-calculator-over-an-algebraic-calculator/ http://calculatorauthority.com/why-use-a-reverse-polish-nota... >For example, we want to compute “(13+3)÷(4×2)” using a calculator of algebraic notation (not a scientific one) then we have to do many steps to reach the answer. Firstly, we have to compute “(13+3)” and then we will save the answer to the memory of the calculator. Then we have to compute the calculation in the denominator i.e. “(4×2)” and we have to save this answer too to the memory of the calculator. In the end, we will bring both the answers and will perform the last operation of division. This procedure has taken a reasonable amount of time. This thing can be avoided by using RPN calculator. In RPN calculator, we have to insert just a single line expression as “13 Enter 3 + 4 Enter 2 × ÷” and the answer will be computed instantly. More generally the use of a stack (in the case of some calculators an actually visible stack) helps a lot with complex formulas.
bfirsh 9y ago
My favourite HP calculator stories: Woz sold his to fund the development of the Apple I, and they were used in the later Apollo missions as a backup computer. http://www.foundersatwork.com/steve-wozniak.html http://www.foundersatwork.com/steve-wozniak.html https://hpinspace.wordpress.com/2009/07/16/hp-65-and-apollo-soyuz/ https://hpinspace.wordpress.com/2009/07/16/hp-65-and-apollo-...
waynecochran 9y ago
When I started college in 1985, every Physics student had an HP41C. You were at a distinct disadvantage on an exam if you had an infix calculator. I still have my HP41CX that my dad bought me in 1985. Now I don't see any of the students using them. What happened? When I used to teach, I would write a large expression on the board and challenge students to a calculator duel -- me using my 1985 HP41CX and them using their lumbering infix calculator. I would always win. The magic is the automatic saving of subexpressions on a stack. Once you got the hang of it, you would never want to go back to an infix calculator. I have the HP41C app on my iPhone, but you miss the beautiful haptic feedback keys that the HP calc's had. Actually, the very first programming course I ever took was a 2 credit course called "Programming Calculators" and we learned to program to the HP41. When a program was running, a little "bird" glyph would "fly" flom left to right across the LCD screen. I remember writing a program to get the bird to fly backwards. Silly, but fun. Of course I had the Math Module that you could plug in and the magnet card reader. Anyway, I always wondered what happened in the intervening time that no one seems to use them anymore.
- jhbadger 9y ago
  Basically after the merger with Compaq in 2001, HP lost interest in their calculators. They still technically sell them, but they aren't advertised to any degree. Obviously since the advent of the smartphone the need for dedicated calculators is lessened, but as you say, the haptic feedback is nice and TI seems to be still selling a lot of calculators.
  - deleted 9y ago
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  - keenerd 9y ago
    They were dying long before smartphones. Cheap Casio calculators happened. I have a little $15 Casio scientific calculator and it has been all that I've needed for college and professional work. But it can take integrals, derivatives and has a general newtonian solver. It covers everything except matrices. Those are miserable to do on any calculator so I'm not missing much. In all my life I've only ever seen two HP RPN calculators. One belonged to my high-school chem teacher, the other to a real estate agent. If there were a $30 RPN calculator with similar functions, I would use it. Edit: 18 years later and they still make it, https://www.casio.com/products/calculators/fraction-and-scientific/fx-115msplus https://www.casio.com/products/calculators/fraction-and-scie... Edit2: Looks like the most readily available RPN calculators are the HP 35S ($55) and HP 12C ($50).
paraplegic 9y ago
My introduction to programming was a 49 step programmable HP-25 which I borrowed from a friend in residence back in 1978, and subsequently just had to have one ... RPN got me interested in taking a FORTRAN course, and the following year I became an undergrad tutor and computer room assistant ... From lunar lander, to star trek on a mainframe, to a career in software development ... funny how career trajectories work ...
aryehof 9y ago
I had a HP-67, then a 41CV which I loved. Then I moved on to the 95LX, 100LX and 12C. Today it's a 12C emulator on my iPhone that I mostly use. I grew up on RPN, and have always considered knowing it as a "strategic" advantage.
ufmace 9y ago
I just sold my two HP48s a year or so ago. IMHO, can't beat 'em for doing anything more than single operations on a calculator. I was willing to sell them partly because I found a nice Android app that emulates one well [0] enough that it seems like a hassle to keep the actual hardware around. [0] https://play.google.com/store/apps/details?id=org.ab.x48 https://play.google.com/store/apps/details?id=org.ab.x48
jeff6845 9y ago
I remember rushing to purchase a HP calculator at employee discount while interning at HP. Most of us did so. A few who had a relative in the medical field, or a spouse going to med school, bought the stethoscope at employee discount. Those two items were status symbol back then.
throwaway7645 9y ago
I have one of the new HP 15c's they created 6-7 years ago. It is the exact same as my dad's from ~1985, but much faster due to the new chip. As great as it is, the Voyage-200 (TI-89 with more RAM, more buttons..etc) would run circles around it for usability. A HP might be able to get the answer first, but with my Voyage the full equation was pretty-printed on the screen and i could adjust each variable without retyping everything.
raminf 9y ago
My dad hired me when I was 14 to help with an engineering project that required calculating thousands of structural tolerances. The job was pretty repetitive once I figured out how to run the formulae using a slide-rule. At some point a relative who was also an engineer was moving out of the country and was selling off his extra stuff. Dad bought what turned out to be an HP-65 programmable calculator, thinking it might come handy for something. He never opened the box and it sat in his office for weeks. One day I came across it and started noodling. Pretty soon figured out you could program the calculator to do the main calculations for my job. What was supposed to be an all-Summer project ended up finished in less than two weeks! (I still got paid for the whole work. Thanks Dad!) That was my first taste of how programming machines can save time. A few years later I bought myself an HP-41C with a card-reader attachment and then discovered 'synthetic programming' (one of the earliest versions of 'jailbreaking'). These were all gateway drugs. Have been hooked on programming ever since. Thanks for bringing back all kinds of fond memories.
ScottBurson 9y ago
If you're an RPN fan and have an Android phone, you might like RealCalc [0]. I use it a lot. [0] https://www.quartic-software.co.uk/ https://www.quartic-software.co.uk/

93 points by ohjeez 9y ago

Still got and use my 12C, and 48gx, unfortunately sold my 28 to buy the latter. When you look at the quality of what HP used to produce versus now, it's very sad.

b5 9y ago
I have a couple of 12Cs -- one made the year I was born, and the other made 2011 -- and an 11C. I use my 12C for absolutely everything, and couldn't live without it. The one made the same year I was born (1983) is a sturdier, but the 2011-made one is also excellent. I also had a 48GX but sold it -- I didn't use it, and I preferred the more compact Voyager series, even if the stack isn't displayed on screen. I agree that the build quality has dropped over time, but I'd still choose an RPN HP over anything else.
agumonkey 9y ago
Yeah they decided it wasn't worth their time, probably because the market shrunk. They could have made money on the education market because their RPN is a wonderful thing but it would require to explain things to kids and teachers .. so now it's all built by another company. I sniped a 48SX on a Craigslist equivalent for 20$, the guy even sold the full manual and 3 math/asm books, I couldn't resist. I'm learning electronics, I plan to mod it if I can, maybe an ESP8266 "coprocessor", a rechargeable lithium bat. and a usb port.
mschaef 9y ago
> When you look at the quality of what HP used to produce versus now I was always impressed that the keys used two color injection molding for the primary labels. There was almost literally no way to wear the label off the keys, since the label was built into the plastic.

jimnotgym 9y ago

I'm too young to remember, but it seems the UK calculator of choice was the Sinclair http://www.vintagecalculators.com/html/sinclair1.html http://www.vintagecalculators.com/html/sinclair1.html

b5 9y ago
My dad, who went to Uni in the '70s to do maths and physics, has a Sinclair scientific that looks very similar except has blue LED digits. I don't know the exact model.
- nothotdog 9y ago
  the bright blue LED had not been invented yet, it was probably vacuum flourescent http://www.vintagecalculators.com/html/calculator_displays.html http://www.vintagecalculators.com/html/calculator_displays.h... https://en.wikipedia.org/wiki/Light-emitting_diode#Blue_LED https://en.wikipedia.org/wiki/Light-emitting_diode#Blue_LED
Theodores 9y ago
This article is much like the US rather than the UK history where we had a separate, home grown path. I think I am the last generation to have a legendary calculator in the Casio FX 82A. Nowadays computers have taken over.

userbinator 9y ago

Notice the distinct lack of an '=' button --- HP's calculators have been almost exclusively RPN-based. It's funny to watch other (newer) developers reactions when they ask to borrow the calculator that's usually on my desk (a 42S) and then give it back several minutes later, with a puzzled look on their faces.

b5 9y ago
At my last job, which involved a lot of number work, my boss would often pick up my HP-12C to quickly calculate something we were talking about. Every single time, he'd say, "Your calculator is broken," then put it back on my desk. It became a running joke of ours.
ece 9y ago
A 42S that a high school friend had was how I first learned about RPN and HP calculators. Bought a 48G soon after which I still have. I use the prime app on android now which works well when needed.
agumonkey 9y ago
"you've been stacked" -- HP calc owner Last year I finally read the whole manual (as a teen I only used the symbolic differentiator, most useful and magical to my brain at the time). Since I learned about Lisp, so RPN programming features appealed to me. I realized that: 1) RPN has lambda << 2 + >> means (lambda (...) (+ 2 ...)) 2) RPN has a short syntax for them << a -> a 2 + >> Yes, 1990 HP RPN had arrow notation out of the box. Take that ES6 !
- nemoniac 9y ago
  If you're enjoying that, you'll find even more connections with Forth, also a very cool programming language. https://en.wikipedia.org/wiki/Forth_(programming_language) https://en.wikipedia.org/wiki/Forth_(programming_language)
  - agumonkey 9y ago
    I love stack languages. Forth, Factor, Joy, Cat .. (all the concatenative crew). ps: there are some Chuck Moore talks on youtube that are worth gold. His CPUs are heaven

KGIII 9y ago

I am pretty old. The first computer I touched was an HP. They called it a calculator, my understanding is that this decision was based on the fears people had of computers back then. Hmm... I don't recall if it was the A or B. But, here is a video that is more than you wanted to know: https://m.youtube.com/watch?v=JmTyrS-jfi0 https://m.youtube.com/watch?v=JmTyrS-jfi0 If you're curious, I hated it. In retrospect, it was pretty awesome. At the time, I hated it. I basically hated computers up until the mid-90s. I didn't really like them for another ten years. Now, the relationship is like that of old adversaries that are too tired to fight any longer.

pmoriarty 9y ago

I've never used an HP calculator, but I've recently been getting interested in emacs' calc, which is also RPN. Could someone who's used both talk a bit about how they compare? Are calc and emacs missing something that made HP great?

agumonkey 9y ago
Single hand operation and wonderful click feel of HP calc buttons (before the 49 model of course) ;)
acomjean 9y ago
dc on the unix command line (linux too), is an rpn calculator. I use its non rpn counterpart bc. I've been told they aren't great (buggy), but for simple math they work fine. I used a hp 32S in college, less mistakes make with rpn then entering calculations the other way. though newer calculator allow entering of whole equations ((10 *5)^2)/3 made this less useful. The hand helds are more portable than emacs.
tyingq 9y ago
You can try an HP48 here: http://www.poleyland.com/hp48/index.html http://www.poleyland.com/hp48/index.html
mschaef 9y ago
Interesting you ask.... Emacs Calc was inspired by the HP-28. https://www.gnu.org/software/emacs/manual/html_mono/calc.html https://www.gnu.org/software/emacs/manual/html_mono/calc.htm... It's not the same, but having used both, they are very similar in overall feel. > Are calc and emacs missing something that made HP great? A couple things: First, having specific hardware is (was?) a nice thing. Secondly, the HP28/48 programming model was very, very orthogonal. It was a more impoverished Lisp than even elisp is today, but it pervaded the entire software stack. While people referred to 'RPL' and 'System RPL' with two different names, the truth is that there was no real distinction between the programming language you used as a user and the programming language used by HP to build the machine in the first place. This kind of solidity and general 'gestalt' pervaded the operation of the machine and made them joys to use.

jaclaz 9y ago

Probably I will sound like a dinosaur, but I actually remember a time where the HP-97 was a daily used tool at work. 256 steps of program! I could write small programs that calculated coordinates for road topography, circular curves and even (with a very little approximation) clothoids. And you will have to pry out from my cold, dead hands my HP 28C[0][1], I bought it right when it came out in 1987 (yes, that is exactly 30 years ago) and it still goes strong. But to give you a data point, I payed for it (in 1987) around 650,000 Lire, something like the equivalent to 330 Euro that nowadays would be roughly 750 Euro. [0] https://en.wikipedia.org/wiki/HP-28_series https://en.wikipedia.org/wiki/HP-28_series [1] http://www.hpmuseum.org/hp28c.htm http://www.hpmuseum.org/hp28c.htm

tzs 9y ago

I never personally saw this, but I've been told by people that the HP-41 could be massively overclocked at the cost of heavy loss of battery life. Supposedly they could be overclocked sufficiently to handily beat common minicomputers, such as the PDP-11, at floating point. Allegedly some people hacked interfaces between their PDP-11 and their overclocked HP-41 that allowed the PDP-11 to use the calculator as a floating point coprocessor.

hota_mazi 9y ago
Correct. The HP 41 had something called "synthetic programming", a flaw that someone once found in the calculator that allowed access to a lot of its internals, including brand new opcodes and capabilities (even graphics, which the HP 41 didn't officially support). The downside was that doing the wrong thing could cause the calculator to shut down sometimes for days in a row. I once did that to my father's calculator and these were the longest days in my life, dreading that I might have broken his $300+ purchase for silly programming antics.

dm319 9y ago

Getting good condition HP calculators can be quite expensive second hand. People interested in buying a new one should check out swissmicros [1]. They are bringing out an HP42s clone with quad precision decimal accuracy, which I'm looking forward to! [2] [1] http://www.swissmicros.com/ http://www.swissmicros.com/ [2] https://www.youtube.com/watch?v=8LatjXPgLI8 https://www.youtube.com/watch?v=8LatjXPgLI8 EDIT: I don't have any involvement with swissmicros apart from anticipating their new calculator

zokier 9y ago
One thing that has always befuddled me with HP calcs is their model numbers that don't seem to follow any rhyme or reason. How does the functionality of DM42 compare to for example WP34? And how does -48 compare, besides the relatively useless graphing capability? I see lots of people also preferring some other models (15, 16, 35, 41 etc), which I would have imagined to be strict subsets of these "juggernauts", but maybe that is not the case?
- brians 9y ago
  The 48s show you four rows of stack at a time, and can use that to show a single long expression. That can be a huge difference—though of course, unlike the time when these were built, we have Octave and similar right there.
  - zokier 9y ago
    DM-42 seems to also feature multiline display (I'm kinda assuming that it will be showing the stack?), so that advantage is mostly negated there?
- dm319 9y ago
  The 48 was quite a bit bigger than the 42s, which I think is the main downside. A bit of googling suggests the 48 contains similar features to the 42s, and probably more. It can also show the full 4 level stack - the 42s showed 2. However, you're looking for the best all-round scientific calculator (form factor restricted!) the 42s probably wins. The voyager series (including the 15 and 16) were well-made and in landscape format, which is nice for using on-the-go with both thumbs. They are more simplistic though - you see one line of the stack, and there aren't menus - hence several variations to cater for different markets. The HP41 was an impressive programmable calculator for its time, and seems to be more expandable than the 42s. However, the 42s is programmable, has a few more features and a more modern display. Not sure about the WP34, though if you look at the cost of a second hand 42s, you'll see that many people rate it much higher than more modern HP calculators. I think what puts me off more recent calculators and even some other HPs, is the ambivalence about RPN. I really like RPN, and don't like when the UI is compromised to please both. [1] http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv005.cgi?read=9278 http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv005.cg...

protomyth 9y ago

I miss the HP-16C. It was an amazing thing to have something with hex. It was pretty useful when I was doing assembly.

paraplegic 9y ago
A GREAT calculator. I wrote a portable forth which I use for hex conversion which I still use frequently.

wslh 9y ago

I just bought a new HP 12C to replace the calculator app. I love the form factor, mainly the keyboard, but they could improve the product adding more memory for programming. It is odd they have an emulator in place to run the original ROM! BTW I have also a HP 48GX but some buttons become unusable. What is the best shop to repair it?

noonespecial 9y ago

I'm a young-un in the HP world. 48g was my first and still only. But you can pry it from my cold dead hand because the snap of those lovely keys under your fingers and that stack scrolling up that screen is the visceral feeling of math.

siberianbear 9y ago

Wow, this is bringing up some memories of my childhood. One of my childhood friends had a father who was a licensed surveyor and civil engineer. He showed me how to write programs one one of these calculators. I was fascinated with it, and started writing simple programs to do obscure calculations. After I showed him what I had figured out, he showed me how to remove the faceplate and access a special test mode by pushing some hidden buttons near the . key at the bottom. In retrospect, I can't figure out how some civil engineer in a rural area knew how to access and use these test functions. Probably, he had a friend from the university who worked at HP or something. I remember that these calculators use something called RPN (Reverse Polish Notation). To do "3+4" you enter 3 <enter> 4 <enter> + <enter>. I had a university professor ask once, what's the opposite of RPN: when you enter "+ 3 4"? One other student answered "Reverse Italian notation?" And everyone in the class laughed so hard...

MegaDeKay 9y ago
Actually, to do "3+4" you enter 3 <enter> 4 + That's it. Note that this is one keystroke less than the regular calculators used by mere mortals, and that is why RPN rules. Source: my daily driver HP-15C that I've had since around 1985. Works perfectly and has only gone through two or three sets of batteries. I'd swear it was solar powered.
- ZenoArrow 9y ago
  Isn't that the same number of keystrokes? [3] [+] [4] [=] [3] [Enter] [4] [+] Both use four keystrokes.
  - jaclaz 9y ago
    Yes, bad example. See here: http://calculatorauthority.com/why-use-a-reverse-polish-notation-calculator-over-an-algebraic-calculator/ http://calculatorauthority.com/why-use-a-reverse-polish-nota... >For example, we want to compute “(13+3)÷(4×2)” using a calculator of algebraic notation (not a scientific one) then we have to do many steps to reach the answer. Firstly, we have to compute “(13+3)” and then we will save the answer to the memory of the calculator. Then we have to compute the calculation in the denominator i.e. “(4×2)” and we have to save this answer too to the memory of the calculator. In the end, we will bring both the answers and will perform the last operation of division. This procedure has taken a reasonable amount of time. This thing can be avoided by using RPN calculator. In RPN calculator, we have to insert just a single line expression as “13 Enter 3 + 4 Enter 2 × ÷” and the answer will be computed instantly. More generally the use of a stack (in the case of some calculators an actually visible stack) helps a lot with complex formulas.

bfirsh 9y ago

My favourite HP calculator stories: Woz sold his to fund the development of the Apple I, and they were used in the later Apollo missions as a backup computer. http://www.foundersatwork.com/steve-wozniak.html http://www.foundersatwork.com/steve-wozniak.html https://hpinspace.wordpress.com/2009/07/16/hp-65-and-apollo-soyuz/ https://hpinspace.wordpress.com/2009/07/16/hp-65-and-apollo-...

waynecochran 9y ago

When I started college in 1985, every Physics student had an HP41C. You were at a distinct disadvantage on an exam if you had an infix calculator. I still have my HP41CX that my dad bought me in 1985. Now I don't see any of the students using them. What happened? When I used to teach, I would write a large expression on the board and challenge students to a calculator duel -- me using my 1985 HP41CX and them using their lumbering infix calculator. I would always win. The magic is the automatic saving of subexpressions on a stack. Once you got the hang of it, you would never want to go back to an infix calculator. I have the HP41C app on my iPhone, but you miss the beautiful haptic feedback keys that the HP calc's had. Actually, the very first programming course I ever took was a 2 credit course called "Programming Calculators" and we learned to program to the HP41. When a program was running, a little "bird" glyph would "fly" flom left to right across the LCD screen. I remember writing a program to get the bird to fly backwards. Silly, but fun. Of course I had the Math Module that you could plug in and the magnet card reader. Anyway, I always wondered what happened in the intervening time that no one seems to use them anymore.

jhbadger 9y ago
Basically after the merger with Compaq in 2001, HP lost interest in their calculators. They still technically sell them, but they aren't advertised to any degree. Obviously since the advent of the smartphone the need for dedicated calculators is lessened, but as you say, the haptic feedback is nice and TI seems to be still selling a lot of calculators.
- deleted 9y ago
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- keenerd 9y ago
  They were dying long before smartphones. Cheap Casio calculators happened. I have a little $15 Casio scientific calculator and it has been all that I've needed for college and professional work. But it can take integrals, derivatives and has a general newtonian solver. It covers everything except matrices. Those are miserable to do on any calculator so I'm not missing much. In all my life I've only ever seen two HP RPN calculators. One belonged to my high-school chem teacher, the other to a real estate agent. If there were a $30 RPN calculator with similar functions, I would use it. Edit: 18 years later and they still make it, https://www.casio.com/products/calculators/fraction-and-scientific/fx-115msplus https://www.casio.com/products/calculators/fraction-and-scie... Edit2: Looks like the most readily available RPN calculators are the HP 35S ($55) and HP 12C ($50).

paraplegic 9y ago

My introduction to programming was a 49 step programmable HP-25 which I borrowed from a friend in residence back in 1978, and subsequently just had to have one ... RPN got me interested in taking a FORTRAN course, and the following year I became an undergrad tutor and computer room assistant ... From lunar lander, to star trek on a mainframe, to a career in software development ... funny how career trajectories work ...

aryehof 9y ago

I had a HP-67, then a 41CV which I loved. Then I moved on to the 95LX, 100LX and 12C. Today it's a 12C emulator on my iPhone that I mostly use. I grew up on RPN, and have always considered knowing it as a "strategic" advantage.

ufmace 9y ago

I just sold my two HP48s a year or so ago. IMHO, can't beat 'em for doing anything more than single operations on a calculator. I was willing to sell them partly because I found a nice Android app that emulates one well [0] enough that it seems like a hassle to keep the actual hardware around. [0] https://play.google.com/store/apps/details?id=org.ab.x48 https://play.google.com/store/apps/details?id=org.ab.x48

jeff6845 9y ago

I remember rushing to purchase a HP calculator at employee discount while interning at HP. Most of us did so. A few who had a relative in the medical field, or a spouse going to med school, bought the stethoscope at employee discount. Those two items were status symbol back then.

throwaway7645 9y ago

I have one of the new HP 15c's they created 6-7 years ago. It is the exact same as my dad's from ~1985, but much faster due to the new chip. As great as it is, the Voyage-200 (TI-89 with more RAM, more buttons..etc) would run circles around it for usability. A HP might be able to get the answer first, but with my Voyage the full equation was pretty-printed on the screen and i could adjust each variable without retyping everything.

raminf 9y ago

My dad hired me when I was 14 to help with an engineering project that required calculating thousands of structural tolerances. The job was pretty repetitive once I figured out how to run the formulae using a slide-rule. At some point a relative who was also an engineer was moving out of the country and was selling off his extra stuff. Dad bought what turned out to be an HP-65 programmable calculator, thinking it might come handy for something. He never opened the box and it sat in his office for weeks. One day I came across it and started noodling. Pretty soon figured out you could program the calculator to do the main calculations for my job. What was supposed to be an all-Summer project ended up finished in less than two weeks! (I still got paid for the whole work. Thanks Dad!) That was my first taste of how programming machines can save time. A few years later I bought myself an HP-41C with a card-reader attachment and then discovered 'synthetic programming' (one of the earliest versions of 'jailbreaking'). These were all gateway drugs. Have been hooked on programming ever since. Thanks for bringing back all kinds of fond memories.

ScottBurson 9y ago

If you're an RPN fan and have an Android phone, you might like RealCalc [0]. I use it a lot. [0] https://www.quartic-software.co.uk/ https://www.quartic-software.co.uk/