EEVblog

Review and teardown of the Casio FX260 Solar II pocket scientific calculator. How good is a $9 scientific calculator?
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[@unacomn]

I haven't seen someone this excited about a calculator since I was 10 and it was me.

[@TheTruthSentMe]

You should watch some Numberphile videos then. They've got calculator unboxings.

[@pnjunction5689]

Matt Parker also gets pretty excited about calculators.

[@McTroyd]

I still have the first TI calc I bought when *I* was ten... a TI-1706 III. Early 90s vintage, and the first piece of electronics I bought. Followed me through virtually all of my schooling, still functional and largely intact (if a bit yellowed) -- found it and pulled it out for this video. First graphing calc was a color Casio, and I loved that thing, but it was stolen. Sad day.

[@Crazytesseract]

unacomn count me in

[@qwertykeyboard5901]

@CHRISTOPHER HANSON They _are_ little computers!

[@luppa79]

I like the degrees-minutes-seconds-button. It's very useful when calculating time, you don't have to use it for angles.

[@StefanGotteswinter]

Always hated that pi is a secondary function.

[@xenonram]

Stefan Gotteswinter The TI-30x/xs/ xs pro/a/2s all have pi on its own key. (P.S. Never thought I'd see you here.)

[@okaro6595]

Old Casio calculators had EXP and Pi on same key but neither was through shift as the calculator can determine which it is on the context.

[@FBarny]

I use the TI30X II in the shop and it works OK for me. We are here more TI people. hardly any shop sells Casio calculators. And yes. it has a dedicated PI key.

[@EEVblog]

Andrew Delashaw - But the TI-30x et.al has the exponent key as a shift function, dumbest idea ever. I'll never use a TI for that reason alone.

[@StefanGotteswinter]

I come around quite a bit ;) Cant get myself around to use a TI calc. never liked the look/feel/everything on them ;)

[@guygadbois1068]

Why am I watching a review on calculators? is this my life now?

[@EEVblog]

Better than what's on TV

[@brucejones2354]

EEVblog. Boy, you got that right!

[@GRBtutorials]

If you were a calculator fan like us you'd understand it.

[@christodd3361]

I can't explain why this is so cool, but it just is. My wife thinks I'm insane. @@EEVblog

[@Crazytesseract]

@@christodd3361 Even mine! Sometimes I get a strong feeling I designed Casio calculator key layouts in my *past life !!*

[@MultipleMonomials]

Man, I love this calculator! Got me through all of middle school and most of high school, and years later I still carry it around as a backup for my TI-Nspire. It is truly a mind-bending value, a serviceable scientific calculator for such a tiny amount of money.

[@GeoffreyVonbargen]

Similar story here, but the Nspire was never as quick to do fast math on, and I've basically replaced the Nspire with Mathcad or Smath studio on the PC.

[@jakegingrich7214]

This I one of those crazy times where I typed in an obscure question about why they replaced this calculator and your video popped up. Thank you for your love of calculators. I hope it's just as awesome as the old one. I'm in construction, so I use the fraction key all the time.

[@17thSzAdDaM]

Thanks for the review!

[@alexadamov2332]

Thank you very much for your detailed review.

[@bwzes03]

My dad used to have an 1977 Casio fx-29 with the green vacuum fluorescent display, battery and mains brick powered. Beautiful to look at.

[@CornishMiner]

Excellent video.

[@trevortjes]

I sure need my stealthy calculations

[@fsmoura]

you just never know . . .

[@wizpin]

Finally, the video I was waiting for.

[@benkasminbullock]

You can sometimes get the segments working on old LCDs by heating the LCD with a hair dryer then squeezing it.

[@williamleinonen4888]

I'm an FX 260 Solar user since it came out. Great deal. Can't read the numbers on the one I have now, but I have the layout basically memorized after so many years.

[@SproutyPottedPlant]

Your recent videos have given me calculator fever, bought the 991EX, hoping to learn how to use it.

[@kippyjohnson]

Would you be interested in doing a "how to use calculators for electrical engineering calculations" tutorial?

[@ghostunix731]

@kippyjohnson All you have to do is find the medium of amperage vs voltage which is associated with average wattage. You can determine the kwh based of mean over integer of the electronics devices.

[@cypherf0x]

I bought a SwissMicro DM16L programmer's calculator and love it. I do a lot of embedded programming and it's so nice having it in front of me between my arms as it will do one button conversions between hex, dec, oct and bin. It will also gives you 1 and 2s compliment along with unsigned. It can check just about any logic operation you can think of. It's also a reproduction of an old HP calculator using RPN so it's win/win for workflow and geek cool.

[@DmM843]

"I don't want a degrees minutes seconds button! Unbelievable! And the hyp button! Don't get me bloody started on the hyp button!" :D These two buttons did really save my life in an astrophysics exam, tho.

[@mortabellaful]

I think it was the old fx-260 that had this feature that I really miss on (all?) the new ones. You enter a number, hit "+" two times and with every "=" you get your number added again to the result. Is there any calculator still capable of doing that? It is so useful if for example you have to drill a couple of holes with same distance. No need to move the ruler while being more accurate when marking the drill spots.

[@matteo234321]

At 5:35 when you typed pi to 8 decimals faster than it could display it....... I slowed down the footage and you LITERALLY typed pi accurately faster than it could be displayed on the LCD. Respect.

[@fsmoura]

I still have mine from the early nineties. The FX-260 Solar is an amazing little cheap calculator, very light, charming and pleasant to use; I love it so much. It's still great for situations where you can't lug a hefty HP around. The only sad thing is that going RPN is like becoming Borg/conjoined-you can't really come back, only pretend (badly).

[@AmRadPodcast]

I LOVED my casio back in the college days.. but I couldn't remember the model number; fx-260 solar. Thanks Dave!

[@jordansean18]

Dead serious the FX 260 has been my calculator of choice for at least 15 years. I got the new solar II because of this review and its just as great 😀

[@tenlittleindians]

I've got a fx-300s that's very much like your Tandy. It must be 20 years old! I had to change the battery in it a month back as it would only work in bright light with the old battery. Being a machinist I prefer the smooth gray as it's easier to keep clean around cnc's. The numbers are almost wore off the keys from use. I've got the smaller form factor gray old Casio like yours but prefer the bigger older one.

[@dewickt]

Still have and use my CM100, came in real handy back when I was doing discrete logic design.

[@AmericanLocomotive1]

I used an fx-260 solar all through high school and college - as in until just last year! I actually had two of them. There were actually two different fx-260 solars, both with the same name. The first generation I had used soft buttons, and the 2nd generation I got later had hard buttons and the chassis was slightly larger.

[@MateuszJagocha]

My GF bought me new old stock CM-100 for birthday. Awesome calc, very useful for microcontroller stuff. I love it

[@michaelpiotrowicz6100]

Beautiful Dave. I have an original FX260 on my bench, when the new model can be had in Australia for a decent price I will add it to the mix. VPAM and RPN make my brain go all mushy.

[@trixter192]

I have the OG 260, it came with a cover as well. You can see the slots on the sides on yours to receive it.

[@JerryDodge]

Awesome vid, thanks again! How about some TI-83 and such graphic calculators?

[@mgscheue]

As a teacher, it always bugs me that TI has such a lock on that market. Textbooks are written specifically for their calculators, students are required to buy them, etc.

[@xenonram]

Mark Scheuern It's a, "damned if you do, canned if you don't," situation. If they didn't have it like that, people's would be bitching, "Why can't they standardize things so students can use their calculator along with the book. They've all got different calculators."

[@mgscheue]

True. And you could argue that HP, Casio, etc. dropped the ball on the education market.

[@Veptis]

Mark Scheuern in my state it's two different Casio calculators that you each need for 2 years only.

[@mgscheue]

Interesting! Cost less than the TI calculators, I imagine. The TIs have been the same price forever.

[@thomsn5670]

Mark Scheuern: In middle school we had calculators from MBO (this brand seems not to exist anymore), in high school it was a Casio (CFX-9850GB) and my University was specialized in Casio Classpad (with CAS). But I know that one of the other high schools in my town have had TI at this time. So it does not seem to be too much concentrated on the TI brand only. (all in the state of Saxony in Germany)

[@reidkeevers]

I still love my Casio fx85m, such a beautiful little machine. Even still has the original cover and box!

[@CliveChamberlain946]

Dave, I imagine with your vintage calculator collection, you append some AM audio sounds from early models. I had a slow old Commodore PR-100 that made great AM sounds just listening to all the shift registers on my radio.

[@tychosis]

Still have my old fx-260, no idea how many years I've had it kicking around. I agree that I'll take a proper handheld calculator over using a smartphone (or PC) every time.

[@worroSfOretsevraH]

Please explain where are you using the xy function on daily basis. Thanks.

[@mikewheeler9011]

For rec → pol conversion. For 2+2i = 2.8... 45° Eg. 2 R→P 2 = 2.8... x→y 45

[@Motorman2112]

I do like having a calculator right there on the bench rather than moving away to another device and then opening the calculator on that.

[@alfoncejean8826]

Motorman2112 except if you are out in the middle of nowhere and you have an urgent need for a bit of possessing power !

[@zaphhood4745]

Cool stuff. Thanks.

[@LazerLord10]

aaannnddd... impulse buy. Had to order it with $25 total in my cart, so I just bought some more 3D printer filament.

[@EEVblog]

It's certainly impulse buy, track on the cart level

[@stevencotton6507]

Still have my fx-451M I got for school (will be over 30 years ago now), it still works, I even have the box and manual, but I believe the constants have been updated since then. Seems they sell for good money now, not that I'm selling. Prefer RPN these days, so I use an HP-35s.

[@jordanmocny2690]

The original fx260 was my go to. It’s so awesome you made this video. I’m debating on paying $10 for the updated model or paying a premium of $20 to get me beloved original hahaha

[@darkguardian1314]

Love reminiscing the 70s and 80s. I loved Casio. Had a couple with my first being fx-61. My last classic was a fx-5000f. I loved running mini programs on it. My newer Casio 9850 Graphing calculator didn’t last nearly as long. It just died for no reason. My guess is one of the components aged. Found others with similar issues online with no resolution.

[@shornk]

Great video. I have the original Solar as well. At your videos time index 14:30 you did the chipset test. My Casio fx-260solar came out with 9.000007164 the same as the Fx-260solar II. Perhaps you had entered the sequence wrong? I'd be curious if it was a button error or a chip differance.

[@monchiabbad]

When benchmarking with the factorial you forgot to first clean the solar cell of the classic calculator.

[@chriswathen9612]

The dedicated 'On' key was the dedicated 'Off' key in the battery powered FX82/FX260 models. I always thought they included it so that they could keep the same keyboard matrix rather than redo it to make use of the extra key for something more useful. Never owned a solar powered model, but I often wondered if they would still turn on by pressing the AC key as with the battery models (or even if the 'ON' key was just implemented as a second AC key and would perform all of it's functions).

[@Petertronic]

I still have my FX-61F, bought it in 1989 when I was doing my BTEC National Diploma in Electronics.

[@appelGeek]

My old FX-82 Solar I got at school (got it one year before all the class had to buy the bloody huge TI-30 eco RS) indeed HAD a hard cover, you can see the grooves on the calculator's side for it. Maybe this the difference between the FX-82 Solar and FX-260 Solar?

[@benediktkohler28]

fx260 was my first calculator in school, fx991EX just got me through my last exams at uni. How times change. Thx Casio for helping me become an engineer ...

[@fanjapanischermusik]

i collect calculators and i have a lot of casios. i even got two of those where you said that they where expensive from ebay. one from a older lady which had written her name on the back of her old calculator and one from a guy. these are very nice pieces. this people have used them for years.

[@OneBiOzZ]

I love how you can see the die and bonding wires under the glob on the newer calculator under the right light

[@EEVblog]

Oh, missed that

[@nonohate]

I have the newest Casio that you are showcasing, it's brilliant, it's good for GCSE's here, it has a simultaneous equation option and it's makes some of the questions really easy

[@nonohate]

The class wiz one

[@guybrown9403]

Your Tandy is identical to my Casio fx-115D which I still use (but the display is going). I really need a new one now.

[@radman999]

Dave, you are totally right on Casios. Definitely the best for EE. That fx-260II is about 8 bucks here in Canada like you say.

[@Crazytesseract]

Great review. The older fx-260 Solar is made in 2004, week 15 to the best of my knowledge (not in 1990) and the newer one in 2017, week 47. Both are printed in 7 segment style. The WL mark on the pcb is more typical of the 2000s. And fx-260 Solar was released in 1996, in Japan, from what I have seen in Japanese catalogues.

[@Sutrabla]

I have a Casio fx-82 Solar (1) with plastic keys. And I have also seen 2 variations of the back cover for it.

[@Sutrabla]

Yesterday I got a Casio fx-82 Solar with the rubber keys and its size is a bit smaller than the other one with the hard plastic keys. Design-wise they are virtually identical besides the design on the slide-on cover. Both are called the Casio fx-82SOLAR FRACTION

[@qwertykeyboard5901]

Really impressive how much both this and the EL-506p pack in. The Sharp and the accompanying clones are more feature rich (hell, they even have complex mode!), I would like an fx-260 solar in my collection!

[@redtails]

I actually prefer the TI calculators. I've had a TI-84 since forever and being able to run custom programs on it, and multi-line display, keeps me coming back. I'd prefer they used NAND instead of SRAM but whatever, how often do you replace the battery anyway

[@DAVIDGREGORYKERR]

Do any calculators use the FFT for multiplying and dividing large numbers.

[@omfghai2u]

You can do sin 30 with the 991ex, don't have to input the closing bracket (but yes, ugly) I often prefer my fx-115w though, can't understand why they removed the quick access to eng.sym/Si units from the 991.

[@diabolicalartificer]

Dave, can you do a video please about how to use calculator's in electrical engineering for numpty's? I use about 1/1000 of my scientific calc's functionality, IE ohm's law and the RC frequency formula. That's it. No idea what to do with the bugger.

[@anorax001]

I used a Casio FX-550 when I was in high school during the 1980's. Great calculator for it's day. Before that I used math table books. After the Casio I progressed to HP graphing calculators like the HP-48SX and my current one which is a HP Prime. Of course none of these are as great as my amazing Curta Type II Calculator (look it up) which I bought via an EBay auction many years ago. ;)

[@macro820]

You should run power usage tests on the new vs old, I wonder if the power is being used more by the CPU or the LCD

[@PPSainity]

While my all time favourite will always be the HP48, RPN FTW! I am partial to the Sharp EL546 series for a smaller everyday use calculator. My EL546L model is still working despite the abuse of being in my work bag. For those who may also love the HP48, Droid48 for Android is really good.

[@jordansean18]

The fx-260 has been my calculator for like 10 years... I dont think I've turned on my TI-84 more than a handful of times in my math work, it's all been the fx-260. Now I wonder what kind of nerd I am that I am enjoying reviews of pocket calculators haha I love that it does stats as a function. Ooooo that new one looks great

[@ponderstibbons3718]

Still loving (and using) the 48gx (rpn), or the old ti-34 as backup.

[@adrianschneider4441]

I wonder, whether a NF type could be hacked to reactivate the fraction function.

[@carlosserraa.12]

If you leave absolutely all the light of the room, how many time the Solar II take to switch off?

[@gnather]

How about the Casio fx-115 ES PLUS with natural -V.P.A.M. I got it at Walmart for $16.00 and use it in my EE classes at University. Works pretty well.

[@rafallasocki4426]

My Casio fx-82TL is with me for last 17 years.

[@gigaherz_]

I have a Casio fx-82MS in a drawer. I haven't used it in like 10 years. I think I had to buy it from the shop at the university campus because I didn't have one for an exam. I do have to agree, the rubber keys from older calculators had a better feel than the hard plastic ones on newer models.

[@danielreynolds2913]

Nice video ty

[@oswaldjh]

In parts of Canada the FX260 Solar is still a requirement for people who didn't get a High School Diploma to take the exam. The GED Testing Service supplies training material based on this calculator prior to testing. The same calculator is supplied by the company at the time of testing. You can't bring your own. Casio must be envious of Texas Instruments that has a strangle hold on the Post Secondary Education System with their TI-84 Graphic Calculator being mandatory for many courses.

[@TheTimeGnome]

The FX260 was the calculator requirement to use at the UoC for engineering and had the shulich stamp on the back. They had a new one a couple years ago but the FX260 was much better and I still use it at work now.

[@JasperJanssen]

I was in high school from 91-97 and ours was the Casio FX-82. There was also a TI equivalent you could use, but it was subtly different and unsupported. I had an FX-115s for a while (same but with solar). IIRC we took our own in back then for exams, but this was before there were widespread calculators with memory and thus potentially cheat sheets inside.

[@Silanda]

Long been replaced, but my old FX-82D is still kicking. The mid '90s batteries are still alive too. Cracking it open again, what's surprising to me is that the chip isn't potted, it's naked on the board. Was this common back then (early '90s)?

[@Crazytesseract]

Yes, many of the 1990s Casio calculators used PCB-less designs (1988 to 1994).

[@kostependrhs]

I do not like these modern lcd digits. Bigger, longer but thiner. Less readable and more confusing. Same for the font used on buttons. I do prefer the 80s style.

[@EEVblog]

Agreed. I still appreciate the larger size though

[@Crazytesseract]

The typefaces used on the 80s and 90s model are classic! Modern ones Myriad is just ok, but the newest one is not that good.

[@fersunk]

I always bring my FX 991ms with me all the time. I really like the 2 line display, make it easier to see what are you doing. I almost feel overwhelmed when using a bloody calculator app. Just Wolfram alpha for graphics and their symbolic calculations (an app that can do integrals, Fourier and Laplace transforms is a godsend).

[@xenonram]

Well, I'm glad I know the min lux each of these calculators will run on.

[@zakofrx]

Any of the smaller ones like this with hex - dec etc...?

[@slap_my_hand]

Casio should really sell calculator apps that are modelled after their best selling scientific calculators. Most of the apps avalible right now are a pain to use, even for simple calculations. I would pay good money for a calculator app that works just like my FX-87DE X.

[@bertblankenstein3738]

slap_my_hand Have you looked at Real Calc?

[@michaelhawthorne8696]

Absolutely, I have the Pro version, it's awesome and so well laid out. Looks like the best casio

[@sonictech1000]

Everyone knows and loves the Casios but I always liked Sharp. The key layout on my ancient el-506d is almost ideal.

[@georgepetrakis7703]

Great channel! If you are still around, maybe you should consider reviewing the "new" Sharp EL-W506T. I think it is superior to Casio FX-991ex

[@o_-_o]

fx-991EX is my cup of tea it serves me well (and it is quite fast)

[@JennyEverywhere]

My favorite Casio was the EC-4016, or the Radio Shack rebadge. It was insanely thin, solar-only, and full scientific. It was damn near indestructible, but not unloseable. I'm still upset that I lost the thing, it was my only calculator for years and years...and while I collect slide rules, a calculator IS faster.

[@igsaturation]

Love the 260 II, got 4 of them about a year ago. They were only $6 when first released.

[@EEVblog]

6 bucks for a name brand calc, crazy

[@koffibanan3099]

What do you use the x - y register shift for? I know it turns 2³ into 3², but I don't see how this can be a daily used function?

[@EEVblog]

When you've done an intermediate calculation and you want to swap the result for the next operation.

[@koffibanan3099]

Thanks Dave!! I ordered one :) (should've ordered a dozen)

[@bertblankenstein3738]

Wow, I know you like the Casio calcs. Maybe obsessed? RealCalc is a great app, it has an RPN option, quite a few features and a few more for the paid version. I do use my HP 15C and I'll dig up my old 80s? Casio today just for kicks.

[@IvoryTowerCollections]

The newer models seem to be going back to their earlier 70s designs where they had black fascia with white backs on them. I've got an old 70s era casio that is just a basic math calc that looks similar. So they actually have gone back to designs they used 40 years ago.

[@AstAMoore]

Yes, but does it justify its name and calculate solar flares?

[@michaelhawthorne8696]

I love the Casio calculator range and have bought recently an FX39 from Ebay. A bit tired looking but the VFD is perfect. I tried the 69! on this device and it took a whole 4-5 seconds to get the answer, Real Calc (Pro) on my Smart Phone did it quicker than was shown on the latest Casios in this video, how things have changed.

[@petermuller608]

That screenshot of German Amazon by an Australian KZbinr about a Product launch in the US by a Japanese company... Caught me by surprise xD

[@robbyxp1]

I want one with a proper Hex pad on it (no sharing of A-F)... but can you get one?

[@danielsullivan87]

robbyxp1 that and 32 digit output... (real 32 bit hex to bin - damn new fangled micros)

[@michaelhawthorne8696]

Check out Real Calc app for Android... has HEX, BIN, DEC, OCT as shift+ /, -, X, +, respectively, really easy to use

[@alfoncejean8826]

I've got a ti-60 that I have been using for years. It's not solar powered but the batery in the thing might outlast me XD.

[@lowfinger]

The Tandy is looking like my trusty Casio FX-115D, which saw me through my ONC, HNC and Degree, spent a lot of time tapping away on that thing !

[@Crazytesseract]

Of course, it is a 115D clone!

[@Veptis]

We got the classwiz in school but only for years 10 and 11 now we have a graphical CX something. I prefer the classwiz due to more functions on its face, for example Abs. And not hidden in the catalog. The way variables work on the classwiz is the best ever for doing similar calculatoins multiple times and it's faster then setting up some spreadsheet.

[@ExtremeSquared]

Found a minor bug on the fx260II: A way to check the internal precision of numbers is to take a known value, and subtract the digits as shown on screen. This will show if any precision is stored beyond displayed value. pi(calculator constant) - 3.141592654 (as displayed) = -0.0000000004 (-4E-10) e^1 (calculator constant) - 2.718281828 (as displayed) = 0.00000000045 (4.5E-10) /\ This shows that pi and e are stored with 11-12 digits (3.1415926536, 2.718228182845), and they are correctly rounded to fit on display. Unfortunately... 1/6 (0.16 repeating6) - 0.166666666 (displayed) = 0.000000000666 (6.66E-10) /\ This shows that this displayed value has three extra hidden places of precision HOWEVER it is rounded incorrectly for the display. The displayed value should be rounded to 0.166666667 Why it rounds for one and not the other is unclear. The Fx115ES handles this correctly with a couple more hidden places of precision. The largest single-computation error I was able to induce with this method was 8.88E-10, and if 888 trillionths ruin your project, you should be using a different calculator.

[@Dreamagine1]

What's the "parallel" button do?

[@radarmusen]

The old was not a dust pit around LCD or solar cells, but of course it then could be scratched easily.

[@poptartmcjelly7054]

Did the sin-cos-tan thingy with my two main calcs. CITIZEN SRP-145T II returns 9.00002786 TI-82 STATS returns 8.99999997 What did you guys get? Don't forget to set your calc on degrees :)

[@Luxcoldury]

The Calculator Forensics RSKEY website Dave forgot to link in the description: www.rskey.org/~mwsebastian/miscprj/forensics.htm the asin(acos(atan(tan(cos(sin(9 function

[@okaro6595]

The hyp key is because it gives six functions with a single key. I use the time calculation often.

[@johnharmon8698]

Please make a full tutorial for scientific calculators. I have no idea what half the buttons on my calculator do!

[@dezeekat]

EEVblog is now EECblog