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Scientific calculators - Page 2

post #16 of 29
Another vote for the high-end TI devices. I had the TI-85 through highschool and college, and it served me well through the Engineering curriculum. I still use it.

Plus, since it doesn't use RPN, you can do some cool things with it in notation that actually looks like algebra. Doing things such as solving polynomial equations (including imaginaries!), and transforming into the frequency domain were also easy.

I haven't used the TI-89, but I would guess it is the next, more powerful, and comprehensive brother to the TI-85.

Happy hunting

post #17 of 29
Thread Starter 
Thanks so far for the comments. I'm just thought I'd dump the current state of my research for comment:

1. On researching the history, the TI graphing calculator I last used had to have been a TI-81, not an 83, so I really have no basis to hold an opinion about the usability of current models.

2. While I'm tempted by the reported easier UI of the TI-89 compared to the HP-49G+, I'm still leaning HP for a number of reasons:

- I'm not wild about languages like FORTH and Lisp, but I despise BASIC. And this is from experience: I've probably written 10K LOC of BASIC over the years, in various dialects.

- The whole BASIC vs. assembly thing produces an artificial division in the community that I thought I had left behind when I mothballed my Apple //c.

- The TI-89 Titanium is a lot more expensive than the HP-49G+. You can get the HP for just $115 at Sam's Club!

3. While I'm coming around toward considering the HP, I'm still not yet ready to give up on powerOne. Since I have an emulated 49G on the Palm, the fact that I can't buy 3 49Gs isn't really an issue. It comes down to whether I really need the extras I'd get in a 49G, and whether I'm willing to put up with an inferior UI to get them. On balance, I think formula entry is still going to be superior on a Treo vs. on a 7x33 line B&W gray LCD.

4. On the Mathematica thing, I'm set on that front for the moment. Wolfram has three educational packages (Calculus Wiz, A New Kind of Science Explorer, and Mathematical Explorer) that are built on top of a stripped-down version of Mathematica. So far, I haven't pushed beyond its limits. Even if you don't need the content that comes with these things, they're a great way to get "Mathematica lite".
post #18 of 29
Wow, people still actually use calculators?


Since leaving school, I've rarely needed a hand calc. I use a free RPN calc on my Mac for the simple stuff, and there's always Mathematica if I ever need to do anything complex (which is pretty much never, these days). My old HP-15C is still sitting in a drawer, waiting for fresh batteries

For what it's worth, I also recommend the HP48G. I was pretty impressed by it and almost bought one a few years back. Unfortunately, the distributor stopped selling it, and by the time they told me (a month after I placed the order), I didn't really need it anymore
post #19 of 29
TI's and Casios were big back when I was at university in late (80's-early 90's), but I could never find a few hundred bucks to buy one for myself. Really, most of the stuff I ever needed done can be done either manually, or by writing a simple C/Java/whatever program. Unless you need to solve a system of equations, I can't find too many uses for one unless you're a student or professional scientist (not engineer, scientist).
post #20 of 29
Just to clarify, having used 81's, 83's, 85's, 86's, 89's, 92's and the new Voyager ones...

The 81 was terrible. My 83 was pretty nice, it could graph and such. The 85 and 86 added the solver, as well as an increased amount of graphing power. The 89 is the 92 minus the keyboard and some memory. The Voyager is the new 92, it has all its capabilites and is a whole lot smaller. It's shorter then the 89 but maybe 1/2 to 3/4 inch wider. If I was looking for a new calculator to buy and I wasen't going for the traditional form factor, I'd get the Voyager.

I use my 89 daily, and I have to change batteries every 9 months (I think... the last time I can remember changing them was right before a test about that long ago). The 89 is the standard college calculator these days. Everyone I know except... 2 people, have a 89 or a 92. None of these have ever broken. They're durable and very ergonomic. It solves MOST of my problems. It does have its quirks, but I rarely had any problems until I started plotting advanced pattern factors or telling it to do matlab level problems by itself. It does all the algebra stuff plus limits, integrals, derivatives, z sums plus some of the useful approximating things like taylor polynomials. Also differential equations, function mins and maxs. It does symbolic or numerical work.

If you couldn't tell, I love my 89 and rely on it for everything. The pretty print thing (where it draws the equations like you would on paper) is rediculouly helpful. I've even carried it around in my coat because I use it so much. I disagree that this isn't an engineers calculator.
post #21 of 29
I too was allowed to use a TI-83 in my algebra/geometry in highschool, and quickly learned of the 89's ability to solve equations EXACTLY, ie : 3(4/5) comes out 12/5, completely stumping any moron who's looking for the decimal value of such a simple operation. (function key enter gives approx decimal) . I've used it for about 4 years, and as long as you actually know the math you're trying to do, it can do pretty much anything.

The difference with the 89platinum is that is has a USB port, instead of the normal TI connector, and the whole thing looks large and ugly.

cheaper too.

I really think that a calculator is very personal, and that what you get used to you never want to give it up. You know it's limitations and it wont slow you down.
post #22 of 29
I researched this same topic a couple years ago. I ended up getting the HP-49 and used it for the first two semesters of college calculus. I like RPN. Then one day I borrowed a classmates TI-89 for a try. Even without a manual (and only limited TI-82 experience from years previous) I was able to use the TI more efficiently -- it just seemed more intuitive. I sold the HP on eBay and bought the TI-89 and have never regretted the decision -- several college engineering years later.

There is no doubt that the TI is the standard today (whereas the HP was a decade ago). There just seems to be much more "going on" with their line of graphing calcultors. The apps are better, more available, etc. Rumor has it that HP is getting out of the high end graphing calcultor business -- the development team based out of Australia was axed years ago...
post #23 of 29
This is sad. Despite having a TI and using it constantly without any regret, I have to say I like HP calculators a LOT more. I have a HP scientific which is hands down the most solid calculator below 20$. It's FREAKING METAL. METAL! That and my dads primary financial calculator is a HP, and he's had that same calculator since he was in college back when dinosaurs ruled the Earth.

It really is a shame, because I bet given the right conditions, HP could turn out their own TI-89 which would be 10 times better.
post #24 of 29
Fwiw, some of the former HP calc folks are aparently starting their own RPN calc company: http://www.hpcalc.org/qonos.php
post #25 of 29
Much thanks! That's quite amazing. The CAD photos are very cool, as well as the amazing capabilities the machine has already.
post #26 of 29
The 49G, to quote Bart Simpson, both sucks and blows at the same time! Itty bitty enter key. Difficult to navigate. Stoneage stat entry. HORRIBLE KEYBOARD!
Went back to my 48GX
HP or death!
(and I use my calculator 100+ times per day. I'm a electronics metrologist)
post #27 of 29
Thread Starter 
It's nice to see you back, bigcat39! I've missed you in the recent DMM threads.

I imagine that the problems you mention affect the 49G+ as well, since the only change I'm aware of is going back to plastic keys instead of rubber, but can you confirm that?

For what it's worth, I've been able to get a 48GX on a try-before-buy basis from Head-Fi member aggiegrads, so I'm not going for a 49 any time soon.
post #28 of 29
This is a fun thread to see.

My first 'fancy calc' was a Sharp EL-5100 - a long skinny thing with a single-line LCD display 50+ characters long. It had 10 different memory locations, algebraic entry - all in 1980.

But I came from an HP family. My dad bought them like other people buy suits. I got friendly with RPN early on. He still has: HP-67, HP-97, HP-85 (the "portable computer" with monitor, tape drive, and thermal printer in one 28+ lb package!), HP-41, HP-10c, HP-15c, and maybe some others since I've been gone.

So, in 1984 I got an HP-15c which I loved dearly.


They are bulletproof, fast, all the buttons are in the right places... at least there's still the 12c but I don't know if it's built as tough as the old ones.

It was stolen off my desk and now I have a 48G. It got me through 2 semesters of calculus, has a slew of built in equations (eyewash, really - looks good on the packaging), has big clicky-feeling keys and has been a reliable machine for over 15 years now. You can get 'em on the bay for <$100. Wish I could say the same about 15c's....

Thanks for the links to the PDA emulators - what'll they think of next?

post #29 of 29
Thread Starter 

HP 30S vs 20S Review

So I decided to get a 30S, mainly out of curiosity, because it's cheap. If nothing else, I figured it could replace my remaining Casio. (An fx-115s)

Despite some gross cosmetic similarities, I didn't expect it to be a 20S replacement. The specs and the price are pretty big giveaways, but I hoped it would be closer.

The thing you notice first is the display:

HP 30S:

HP 20S:

(Calculating tan(89.999999999) in degree mode is a good torture test for calculators, by the way. tan(90) is infinite, and each 9 you add to 89.99... gets you closer to inifinte. Not all calculators behave sanely as the number of nines increases, particularly computer-based calculators!)

The flash on the camera made all the LCD elements show up in the first picture. The next picture of the 30S's display is more "honest". But still, there are still some things you can compare between the two. The 30S does textbook-entry in the top line; when you hit the TAN key, it puts "TAN()" where the cursor was and puts an insert cursor between the parens. The 20S is traditional: you enter the value, hit TAN, and get the answer. Notice that the 20S gives you nice commas as thousands separators, while the 30S uses cheesy apostrophes. Also notice the difference in clarity between the segmented part of the LCD displays. The 20S is the hands-down winner here.

HP 30S:

HP 20S:

Like most calculators, the highest factorial the 30S can calculate is for 69, since it is limited to 10^99 in scientific notation. The 20S's exponential limit 10^499, so its factorial limit is 253!. The main purpose of this comparison, though, is that the 30S does have a nicer exponent display: it's possible to miss that E in the 20S display.

The button layout is very different between the two machines:

HP 30S:

HP 20S:

There are two major differences. One, the 30S only has a single modifier key, which it calls 2nd, like on TI calculators. All of the other functions are available as either "modes" which change the function of some of the keys, or through menus using that 4-way navigation button you see. For instance, the factorial function is accessed via a PRB button (probability), which gets you a menu in the top line, from which you can pick from several functions. The 20S does traditional entry and has two shift keys, so it has no need for navigation buttons. The 30S also uses the navigation button when editing the entry line: this makes textbook entry tolerable. On my Casio fx-115s, there is no navigation, so you must enter the equation correctly from the start.

The 30S has a DEL key that operates rather strangely. When it's at the end of a line, it deletes backwards, but otherwise it deletes forwards. This takes some getting used to. You only need backwards deletes on the 20S, since you can't edit the entry in place.

The memory function behaves quite differently between the two. On the 20S, you have 10 numbered memory locations. Say STO [n], and the current entry goes into that numbered bucket. On the 30S, they STO key brings up a menu, which lets you pick from 10 named memories: A, B, C, D, X, X1, X2, Y, Y1, Y2 and EQN.

The 30S has some common constants built in, including Boltzmann's constant, which we find use for in electronics. The 20S has no constants, but its simpler memory setup makes it easier save a constant somewhere and remember short-term where you put it. The memory on the 30S is geared more towards equation solving.

Speaking of equation solving, the 30S is clearly more powerful here. It's no 48G, but it can do basics like finding zeros in a quadratic, and solving systems of linear equations. The 20S has only primitive capabilities here, by comparison; so primitive that I've never even bothered to use them.

The 30S comes with a hard plastic slip cover, while the 20S has a nice cloth-lined vinyl cover. The 30S does have the advantage of keeping a cheat sheet inside the cover. But I haven't found much need to refer to the 20S manual very often in recent years.

Speaking of manuals:

HP 30S:

HP 20S:

The 30S comes with that most tyrannical of manuals, two map-folded single sheets; that's all. You don't even get a good manual on CD as you do with the 49G+. The 20S came with a "real" manual.

The feel of the keys is a bit better on the 20S, but the 30S isn't horrible. I'd rank the 30S's feel above my Casio fx-115s.

While the 30S is no 20S replacement, it is a reasonable calculator. Its target market is clearly students: the textbook entry, the simplified button layout, the interchangeable colored face plates, the middle-school algebra features, and the hard plastic cover are testaments to this. There's even a place on the back labelled "NAME:" in a box where you can scratch the kid's name into the case.

If you have a need for a basic scientific calculator, or a student that needs a good calculator for school, this is a better choice than any other in its class I've seen. But if you're used to HP calculators of yore and want a new primary calculator, you'll need to look beyond this one.
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