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Recommendations for RPN Calculators?
sg3000 asks: "My trusty old HP 48S graphing calculator, that served me since engineering school, seems to be giving up the ghost. I haven't used it in a few years, but recently I put new batteries in it. It works, but it makes a loud static/white noise sound when it's on. The noise is not as noticeable when I hold it, but when I set it down on a hard surface, it's really loud. Then it sucks the batteries down incredibly fast (I put new batteries in it, and two days later, they were drained). Any suggestions on what I should buy as a replacement?"
"I'm in graduate school now, and since I'm taking an accounting course, where they don't want us digging out our laptops during a test, I need to buy another calculator. I'm a big fan of reverse polish notation (RPN), so I'd prefer to get another HP calculator.
Do companies still make calculators? I'd love to get another HP 48, but I'm not even sure if HP even makes calculators like that any longer -- on their web site, they're all cheapo-looking single line deals. I've read about something called an HP 48g, but HP has nothing about it on their web site."
I have the HP48GX - it's a great calculator, but slow as molasses. According to this page HP will be releasing the 49G Real Soon Now(tm). I'll believe it when I see it, of course, but we can dream, right?
I have a HP 48GX and love it. If you can find one, get one.
I also wrote a GTK based one:
ghsilop.
Sounds like its power supply inverter is toast. Rip it apart, trace down the IC that is making all the noise (or look for a small IC mounted xformer near on IC) and do some home work. Replace what makes noise and what ic is a PWM if it has one, unless its home brew PWM inversion and learn.
That's a good recommendation. I have the 48G, no expansion slot, never needed it. Great calculator and the transition from the 48S is minimal. They revamped some of the applications to make them a bit easier to use, but you can still access the old 48S methods if that is what you prefer.
V
Sorry, should have put the link in easy to click mode: HP 49G+
The RPNs worth buying are:
16C - awesome calculator for programmers, especially embedded work. There is no better number system converter available at any price. No I can't do bin/dec/hex in my head faster than the 16C and neither can you. Expensive due to relatively low numbers produced.
42S - pricey, even used, but excellent. Two line display, a replacement for the 15C.
32SII - somewhat like a 42S but with single line display, not so nice to use.
15C - same form factor as 16C. At the time HP's top scientific.
11C - a simpler 15C
10C - a simpler 11C
All the above have solid old-HP build quality, excellent key feel and outstanding battery life.
Older HPs are also usable (and may be preferred) - but they have even greater collector status and sometimes fetch higher prices. They will go through batteries faster and the red LEDs can be harder to see.
Forget the 48 models, the 49 and all the new stuff. The 48GX is OK if you have to have graphing but the single and dual-line models have better UI for daily use. The 49? HP died when Carly took over. Now they make pretty colored plastic boxes that only work with windows and they have forgotten how to spell "engineering". In fact they fired all the engineers and HP is now run by MBAs in shiny suits.
(I own 16C, 42s, 15C and 11C models.)
This sounds like subharmonic oscillation in the inductor core used in the DC-DC converter. Pop it open, find the inductor, and replace it - thing should be good as new.
Absolutely untrue. They're made by the same calculator division that worked on calculators before HP spun off Agilent. It's just that Agilent got the calculator division.
The division was rebranded, not the calculator.
Jeremy
Looking for a Python IRC bot?
Contrary to what others here (your usual /. cranks with rose-colored nostalgic memories of ancient hardware) may tell you, the 49G is a great calculator despite the flaws in the design of the keys and display as well as the "new-wave" case. However, don't run out and buy a 49G now; HP is finally gearing up to release new calcs: the 49G+ and 48gII replace the aging Saturn processor (2-4 mhz, I forget what the process was but it probably was 3 microns or so) of older HP's like the 48S/SX/G/G+/GX and 49G with an ARM9 processor (48-75 mhz, probably a .18 micron process). (I think the ARM9 doesn't do quite as many IPC as the Saturn, and low-level saturn emulation will give some performance penalty, but still, this is going to be a lot faster- hpcalc.org just states it will be 3-7 times faster than the 49G, that's a pretty wide range). In addition, they appear to have fixed many of the case/key/display problems which plagued the 49G, and battery life should be about the same as it was for the earlier 48/49 series. I have absolutely no doubt that the new calcs will be fantastic deals.
Or just get yourself a PDA running version 5 of PalmOS (lower versions are supported for certain PDAs) and use an emulator to turn the PDA into your old HP48S.
:(
The emulator seems to get good reviews. Unfortunately it doesn't run on my Treo 90.
I'm in the same boat. I've returned to engineering graduate school after 7 years, and I've found an HP calculator emulator at the following website: http://power48.mobilevoodoo.com/
It works really well. Hope this helps.
Buy new(alkaline) batteries for it. I kid you not, it'll speed it up- if you haven't noticed, performance is noticeably dependent upon battery voltage, and the thing crawls when the batteries get low- possibly on purpose, I dunno.
I've had mine since the early 90's, and I never though of it as slow at anything except menus, graphing, and equation solving. For standard math and even running RPN programs, it's pretty quick- I never felt it was a 'hinderance'.
Please help metamoderate.
Reverse Polish Notation?!?!? Why exactly is it "Polish"?
Because a Polish man came up with the idea?
Prefix and Postfix notation were developed in the 1920's by Jan Lukasiewicz (who was, in fact, Polish). Prefix notation was often called Polish Notation in honor of Lukasiewicz.
Postfix turned out to be useful for computer operations, if you made it into a stack and then did operations upon that stack. It was called Reverse Polish Notation, since postfix is the opposite of prefix, and prefix was called Polish Notation.
Simple.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
And there are many occasions where the graphing functions of my TI have proved useful in the workplace. To name a few:
- being able to view every key I've entered before evaluating the expression
- being able to revise and edit incorrect expressions
- to determine linear regression fits for data sets
- to perform functions like logarithms and square roots on said data sets, in order to linearize them (linearity being checked, of course, by the R^2 correlation of my fit)
- anything at all to do with linear algebra, especially solving systems of equations or matrix manipulations. RREF is a bitch by hand.
For more "pure" math (like Diff. Eq.), I agree that pencil and paper are generally easier. But any applied math (a.k.a. engineering) requires an insane amount of busy work that could not be handled with a puny scientific calculator. I know you said Engineering and Physics are different stories, but everything I just wrote could certainly apply to all sciences (even the "soft" ones like Psych. and Sociology), or anything at all requiring data collection.
For the record, I use a TI-86 daily at a bio-tech job. It has the stats capabilities of the 83, plus all the good parts of the 85.
Si la vida me da palo, yo la voy a soportar Si la vida me da palo, yo la voy a espabilar
The calculator is slow to respond and update the screen, but it does have a wonderful type-ahead buffer. Once you're confident with the commands (takes time to memorize) and the buttons (their high quality makes it easier to trust), go ahead and type as fast as you want. The calculator will skip screen updates during this time, so you'll get the answer soon after you stop typing.
Once you know that secret, the speed isn't a problem (and I've got a 48S and a 48SX... that's a 1 MHz processor vs. the 2 MHz processor of the G's)
HIV Crosses Species Barrier... into Muppets
HP's new calculator division is based in San Diego. I was just at the HHC conference this past weekend, and the division director, marketing director, engineering manager, and lead software engineer were there. They seemed to be very concerned about customer feedback and fixing any problems (or perceived problems) with product quality.
Their first new high-end RPN calculator in four years is the HP 49G+, which will be officially announced in the US on October 6. (It's already available in some parts of the world.)
The HP 49G+ has similar capabilities to the HP 49G, but with a larger display (25% more pixels), faster processor (75 MHz ARM), more memory, better keyboard, USB interface, and an SD slot for flash memory expansion.
The problem with the TI units is that they're just downright fragile, and tend to let you down when you need them most.
I've got a 20-year old HP-11C that I still use heavily, also an HP 48G that's served well for a few years. These things have been dropped, spilled on, carried in back pockets, etc with not a single problem. These things are built like tanks.
In the same period of time, my wife, who treats her stuff really well, has gone through over a half-dozen TI calculators. They just don't last. And, even when they do work, they go through batteries at a rate four times or greater than my HPs. Heck, my 11C has only had it's batteries replaced four or five times in 20 years. Having the display on the TI go so dim you can barely see it, because the batteries are getting low, is extremely annoying.