what should a new RPN machine contain?


(This question was spurred by the thread below about contacting HP and urging them not to abandon RPN.)

So -- what should a new RPN (scientific) machine contain in the way of functions?

My own preference actually would be for a simpler function set rather than a more inclusive one. I have a 48G+, and it sits unused most of the time because it's just too @#$%! complicated for routine calculations. Yeah, it's a marvel, but... (I'm a science writer in the fields of astronomy and geology.)

I still have the 35 I bought 30 years ago last month, and it works perfectly. For 95% or more of the calculations I do, its function set is totally adequate. It's biggest drawback -- maybe the only one -- is the rapid battery drain from the LEDs.

At this point, most of the intensive number crunching I used to do on the 35 (and its successors, a 25, a 67, and a 32sII) is now done by software running on my computer. What I need these days is a CALCULATOR, not a calc that's trying to be a handheld computer. I don't know how typical this is, however.

As for me, I'd be happy with a "new HP-35" that has a long, long battery life -- my 32sII is 9 years old and has its original batteries running. Second, I'd like a minimum of prefix keys; I like single-function keys.

I bought my 32sII and have used it extensively. It's a wonderful machine. But, jeez, nearly every key has FOUR functions...!?! Ack!

All those for simplicity, please raise your hand....


I am like you. I have 2 48GX calcs, one I carry with me everywhere and one sit on my desk. If it wasn't for the unit conversion they might not get used at all. I am a drafter and CAD user for a city planning office and contantly need to change all sorts of units from one to another depending on how the plat information is listed. I I started out with a 41CX 22 years ago and own or have owned(2)41CX, 15C, 20S, 28S, (2)42S, and (2)48GX. By far the units that I use the most have been the 41CX and then the 42S. If only the 42S had the unit conversions, the read/write IR, and the memory of the 48GX, I wouldn't need any other calculator. The 48 is too complicated to be really usefull. The 42 is almost the perfect calculator.


Unfortunately, the best machine for your needs seems to be the Voyager series' HP-10C !!

Why ? Let's see:

- very small and lightweight, ultra-easily pocketable, one of the smallest HP calcs.

- clear, contrasty segmented LCD display, very easy to read in almost all light conditions this side of utter darkness

- excellent, classic keyboard, molded keys that won't wear off, ever

- incredibly low battery consumption: even using it heavily each and every day, you won't have to change batteries in at least 4 or 5 years, up to 15 years on record !

- only a single prefix key: keyboard totally uncluttered,
many keys have just one function, none more than two

- fully adequate instruction set, including all typical scientific functions, plus linear regression, statistics, factorial, hms conversions, etc.

- classical, 4-stack + lastx RPN, and simple keystroke programmability, for when you need it. Also, memory automatically repartitions between up to 70 program steps, or 10 storage registers (with STO+,STO-,STOx,STO/ storage arithmetic), or any combination in between.

The caveat ? Incredibly hard to find, and then usually at outrageous prices ... but it certainly *is* what you want, so if you can afford one, don't hesitate !


I'd sort of converged on that conclusion myself!

But I'm actually not simply strolling down memory lane here -- I'm trying to see if a consensus exists for some advice to give HP regarding one or two RPN machines to introduce, or reintroduce.

I realize that trying to move the company this way is likely to prove, um, difficult and probably frustrating from our point of view. Any ideas, though?



I second you in a wilder consideration: Voyagers at once.

Each of them, any of them. I'd rather go for an 11C or a 15C because the 10C is, as mentioned, too hard to find (the HP10C has been redefined as a collectible, no longer a calculator). And boh have a bunch of other features that do not clutter the keyboard and are helpfull.

If I'm asked about, I'd rework the Voyagers and launch them again. No changes, with the optional '+' series, say: HP10C+ HP11C+, HP12C+, HP15C+ and HP16C+. or why not having an HP10X? I have my idea about what to add, but I'll allow others have their own.

And let's face it: Voyagers have a fancy design. They resamble the HP71B that is also a "handsome" handheld.



I've consistently recommended the HP-32S as the antidote for those annoyed by HP-32Sii keyboard clutter.

It has a single shift key, with most of the lesser-used functions made available as menu selections.

The alpha register designations don't terribly crowd the keyboard, but do enable a wonderfully straightforward and semi-mnemonic register naming and program labeling scheme.

The character-dot-matrix (not graphic) display (like that of the 32Sii, but slightly smaller) is a nice compromise between seven-segment readability and the requirements for alpha (as well as numeric) presentation. (And the feature I use most is hexadecimal/decimal conversion . . . )

Like the 32Sii, it has the four-level RPN stack, a nice programming paradigm, tremendous portability and essentially infinite battery life.

My only gripe with either has been their limited memory, but I don't program the calculator regularly, so that doesn't matter too much anyway.

If you're put off by the busy-ness of the 32Sii keyboard, by all means, take a good look at the HP-32S!

(And may I note that, in reference to your hopes, "consensus" is going to be hard to come by!)


Local variable scope for RPN programming...



Local variable scope for RPN programming...

Like in an RPL calculator?




Like having a new fresh set of local numbered registers for each function so that you could do whatever operation you like on the numbered registers without being afraid of ruining the numbered registers of the calling function...

Running "MAIN" below would return leave Y:2 X:1
on the stack

Get the concept? Would be really powerful!
(Almost worthy to be called the next generation of RPN programming...)


STO +00
RTN 00 --> pushes R00 on the stack in calling function

STO 00
CALL "ADDONE" (ST X) --> parameters goes into R00, R01...
RCL 00


Hello Robert,

If you're interested in that Voyager series, try looking for an 11c: the 10c is the rarest of the breed. I'm still kicking myself for having given away my old 15c after I started using a 32s (which I still have). I got a 32sii eventually, which I've used a few years, and was disappointed to see it go out of production. The idea of a new hp-35 is nice, and you know, if they had made the lowly hp-6s in an RPN version, that would have been a nice, rugged little day-to-day scientific.


I have a 41CV, 42S, 48G, and a new 48GX. The ultimate RPN machine would combine the best of these.

Form factor like the 42S, put perhaps with a 3 or 4 line display.

Keypad layout like the 41CV with the arithmetic keys on the left. After barely touching my 41CV for almost 10 years, my fingers still know where the plus key is.

Complex number handling like the 48's.

Native olynomial root finder. This is one of the things I miss from the 48's when using my 42s. My 41CV has it with the math pac. The solver in the 42S is ok otherwise. 99.99% of the time if I want roots, I want all of them, and I have a polynomial.

Something for HP to consider would be to make the calculator switchable between RPN and algebraic entry. When I was teaching, I always had a few students bring in two calculators. The 48G(X) was to handle the complex numbers, and they used whatever other calculator they had for everything else. You would see them do calculations using the algebraic calculator, type results into their 48G, do some complex math, and then copy those results back to the algebraic. RPN is the Way, but it does take some getting used to.


Something for HP to consider would be to make the calculator
switchable between RPN and algebraic entry.

Well, it did just that in the 49G. Unfortunately, it did a lot of other
things in the 49G that many of us aren't pleased with.

When I was teaching, I always had a few students bring in two
calculators. The 48G(X) was to handle the complex numbers, and they used
whatever other calculator they had for everything else. You would see
them do calculations using the algebraic calculator, type results into
their 48G, do some complex math, and then copy those results back to the
algebraic. RPN is the Way, but it does take some getting used

I guess that those students just didn't understand that the RPL
calculators can handle algebraic objects just fine. RPN is indeed the
way, but when you already have an algebraic expression from a handbook
or textbook, it may well be easier to simply type it in as an algebraic



I have a 48G+, and it sits unused most of the time because it's
just too @#$%! complicated for routine calculations. Yeah, it's a
marvel, but... (I'm a science writer in the fields of astronomy and

Too complicated??? Maybe it's because my first HP was a 28S, but I find
the RPL calculators quite simple and easy to use. To be sure, you can
choose to use complicated methods to achieve what you want, but you can
also use simple methods, at least for "routine calculations". Usually,
it's a trade-off amongst ease of understanding, number of keystrokes,
speed of execution, the amount of memory needed for execution, and, for
programs, program size. It does often give the user many different ways
to accomplish a given task, and it has many commands that I just don't
have the mathematical knowledge to make use of, but complaining about
these things would seem much like a prospective groom complaining that
his intended bride is too beautiful. Probably what I find worst about
the 48 series is that a 48 is simply to big for my shirt pockets.

The only calculator I have that might be considered "Classic RPN" is the
16C that I inherited from my brother, and I really haven't used it much.
Interesting, and it has some useful "binary" commands that aren't
built-in to the RPL calculators. But I strongly suspect that many things
that I find easy on a 48 series would be somewhere between difficult and
impossible on a "Classic RPN" calculator.

One of the things that I would very much like to see is a very basic RPN
"4-banger" with just +, -, *, an / operations. Maybe square root as
well. Something very low-cost that an elementary school student would
use when just learning to use a calculator, before they're indoctrinated
into putting the operator between the arguments.



Another vote for simplicty. Not simple simplicity. Not simple-minded simplicity. But elegant simplicity - the kind that was evident throughout the Classics and culminated in the 41CX.

However, what might be even *more* important than what is in the calculator itself is what comes in the box *with* the calculator. Last week, I finished the novel I was reading, and looking for something to relax with before going to sleep, I pulled the 41CV "Owner's Handbook and Programming Guide" off the shelf.

It reminded me again of why I always bought Hewlett-Packard calculators - and, in fact, why I made my career in technical writing and journalism: clear explanations and examples, use of colour to clarify functions, keys, etc., elegant (and even witty) use of illustrations at the facing page of each chapter. Spiral binding so the book will lie flat while in use.

I'd quite often pass through Singapore Airport, where the duty-free stores had HP calculators, and the sales people were always surprised when I'd ask to see, not the calculators in their display cabinets, but the *manuals*. You could never form an impression of the power of the HP-41CX from a two-minute session of uninformed key-prodding.

So, I'd say to HP: something like the 41 would be the sweet spot for me, and, I'd say, most of us. But regardless of the actual functionality: bring back good manuals! The 'thing' that accompanied the 48GX reminded me of a 1920's high school mathematics textbook in layout and typography, and had about as much character. And as for the 21-page travesty that accompanied my son's HP-6s . . . Well, it was about as good as that calculator deserved.


--- Les [http://www.lesbell.com.au]


Here's another one of my rants, brought on by my two recent HP purchases.

When I buy products, I want to find a manual inside that will explain every function the product has. It doesn't have to be pretty, just robust and comprehensive.

I have recently been disappointed by the quality of the "manuals" included in two recent HP purchases.

My new HP deskjet printer didn't come with a manual, it came with a "placemat" that provided instructions (well, actually it provided pictures) on how to get started. I had a couple of questions regarding the buttons and lights on my printer, so what was I forced to do? DOWNLOAD a .pdf of the manual from HP!

In another instance, my friend needed a calculator for a finance class; I offered to lend him one of my 12Cs, but his ability to learn RPN is comparable to Michael Jackson's ability to fake sanity, so I went with him to buy a 10BII. When we finally got the blister pack open, what fell out was not a manual, but a fold-out instruction "sheet"; it resembled something that came with a $5 Timex watch!

Now, I often said that I'd no longer be "cool" when I hit 30, and I guess it's true. It must now be hip to NOT include manuals with products, and the new HP obviously personifies hip!

P.S. Since I'm putting this in a thread on what a new RPN HP should include, I should probably throw my 2 cents in...I love Voyagers, but I also think that the Pioneers had an early death. In my opinion, there were many more years left in that range! I'd love to take the 17BII, add more memory and make it a dedicated RPN machine; the '=' key always throws me off!

I know that this may not be a popular position, but I prefer the menus over a cluttered keyboard. Something with two shift keys and all those colours...that's too confusing for us finance types :)


One of my pet peeves is that it seems that as products become more
complex, the documentation that comes with them becomes thinner, and
even at that contains more errors about how the products actually work,
so it becomes harder and harder to use the products to their full

Maybe it's the fear (probably well-founded) that a manual as thick as
the Bible would frighten off many potential purchasers. Or maybe they
reason that the vast majority of purchasers would never get around to
reading the manual anyway. Perhaps providing only a thin "Getting
started" pamphlet makes it look as if using the product is so intuitive
that comprehensive documentation isn't needed?

Of course some software products come with built-in "Help", but more
often than not I find the "Help" to be somewhat less than helpful.

Oops! I almost forgot. As part of their environmental policy, they
minimise the use of paper products. So the purchasers (well, those who
want hard-copy documentation) have to download the documentation and
print it out on their own paper.

Of course with the 49G, there's the issue of having the OS in flash
memory. When a new "ROM" revision is released, should HP be required to
print and send a new manual to everyone who already owns a 49G? I don't
think it would be feasible to do that, but they could at least make a
well-written downloadable and printable "e-manual" of some sort
(presumably PDF), updated to the current OS revision and with known
errors corrected, available.

Note that HP is not alone in this regard.



>Note that HP is not alone in this regard.

Of course not. I think Microsoft started the trend when it stopped including manuals for its Windows and Office products.

Now *there's* a complicated product, and you have to read Help text to understand it.

I wish I could say that Apple Computer is better, but it ain't. OS X comes without a manual. You pull down the Help menu and chances are that the help text you need to read must be downloaded from Apple's web site.



Pioneer case- easier to "thumb" in the field, IMO.

slightly bigger display (I think a modern machine could squeeze it in_ to show 4 stack levels or 3 stack levels + softmenu

configurable stack (modes menu. 4 level, 7 level [xyz, alpha beta theta, and T], and 48 style object stack.)

one shift key, good menus, but *absolutely* an alpha key.
(I can deal with 2 shift keys fine in the old colors. I'd prefer it, but I understand people not liking it)

modal switching to give the ability to code in both an improved RPL and a keystroke model similar to the 41/42

real I/O via infrared.

128k minimum memory- 512K would be better (with that level, you could compete with the mig educationals, as well. with I/o, you get fulluse of the popularity boiost of an internet connected developer community)

MANUALS! Real, multi volume, *pocket sized* manuals. I'll cary 1000 pages of docco around if it fits in my wasitpack field bag or m65.

(and the finance, matrix, and stats data has to be able to translate into csv ascii.)

sound like a lot- it's 10% of what a palm can do, so it's not impossible.


The current trend not to include manuals is dangerous. Forcing users to download documents is presumptuous -- not every user will have internet access!

Like you, I also think that manuals should be complete (explaining everything), clear, and well-written. Like an HP-67 manual, or 41C. But even the 48GX has incomplete manuals and as for the 49G... well, forget it.



Forcing users to download documents is presumptuous -- not every user will have internet access!

It's worse than that. My experience of corporate web sites is that content comes and goes over time, often unexpectedly. So there is no guarantee that the person, to whom you want to sell an item with a downloadable manual in a year or two, will even be able to download the manual, since it might be gone from the site.

Already, HP's official URL for calculators, printed on the back of recent products, bounces you out of the HP corporate site into the HP shopping site. Who's to say that the people running this site will still make available documentation and support materials for discontinued calculators in a year or two? And who's to say it would be wrong for an online store front to stop providing such materials anyway, once the product's been made obsolete?

Yet this leaves future buyers of these machines in a difficult position. At least when printed manuals are shipped with a machine, a buyer can expect to get some documentation with it, or negotiate a lower price because of the missing item. But when documentation becomes downloadable, whose responsibility is it to provide it for future buyers and owners, once the vendor stops shipping the product? Maybe this site will take on that mantle as a natural extension of the CD/DVD collection, but I find it disappointing that it would need to.


This is one area where TI is in the lead. The URL on their calculators takes you to a useful place and they have a reasonable amount of documentation available including for some discontinued calculators. Of course, their calculators don't need so much documentation! (I had to get a dig in - the most advanced TI I have is the 83+SE, their bigger models probably need lots more documentation)


The current trend not to include manuals is dangerous. Forcing users to download documents is presumptuous -- not every user will have internet access!

Funny you should mention that. The most egregious example of said "danger" was the brand new DSL modem a friend of mine bought from a well-known company-who-shall-remain-nameless-but-really-should-know-better. His ISP wasn't using DHCP to assign IP addresses, so we needed to override the default NAT settings in order to establish a connection to the outside world. Unfortunately, the annoyingly limited "management tool" that it shipped with didn't have the ability to modify the NAT settings, referring us instead to the CLI reference manual -- which was no longer shipped in hard-copy form, but was available "in convenient electronic form, downloadable from [their] website."

Imagine our thrill at this added "convenience."


>All those for simplicity, please raise your hand....

I second the motion. A good RPN calculator should be a _calculator_, not a mainframe wannabe. It should have whatever features are truly necessary -- and no more.

Even programmability should be an option. I'm convinced that many HP customers out there have never written a single line of code, and wouldn't know what to do with it if they wrote it.

Graphing should be optional too. This, to me at least, is an important issue. I have no need whatever for graphing, plotting, and the like. Why should I pay a higher price for a calculator full of graphing features I'll never use?

I believe there's room for two _simple_ RPN calculators. A non-programmable, and a non-graphing one. And include a decent manual, please. Maybe HP should rehire the people who wrote the 41C/CV/CX manuals!


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