Casio FX-991EX ClassWiz Scientific Calculator - Page 1
Forum section: electronics / general

author: Technobabble_
author_rank: Regular Contributor
timestamp: April 13, 2019, 04:05:26 am
content: (This is my opinion. Your mileage may vary).The buttons are incredibly shallow and mushy and don't inspire confidence. I tried using it for an hour and I couldn't get used to the feel. Were all Casio's like this? On the other hand, the black matte textured front feels nice.For kicks and giggles, I opened it up. Image attached.

author: Specmaster
author_rank: Super Contributor
timestamp: April 13, 2019, 08:37:40 am
content: Quote from: Technobabble_ on April 13, 2019, 04:05:26 amYes I think all Casios had the same button feel which I quite like TBH

author: Mortymore
author_rank: Frequent Contributor
timestamp: April 13, 2019, 09:25:10 am
content: I have both of those models at home.The latest EX I gave it to my wife and like Dave it was ordered from some indian Ebay seller when I first saw the Classwiz, and now it's my wife favourite calculator. The EX is much faster that any other calculator I have. Later I bought an fx-82ex for my daughter as an upgrade from an HP 10s.About the keyboard... they seem all pretty much alike this days as far as I can tell, but I miss my FX-5000f with it's rubber keys, that I used when I started to learn electronics. I just lost the track of that calculatorThe Classwiz calculators may feel a bit like cheap plastic, but they are great calculators, and for sure some of the fastest in what they do. (if not the fastest)

author: bd139
author_rank: Super Contributor
timestamp: April 13, 2019, 10:21:10 am
content: The 991ex is pretty good IMHO but I had a button failure on mine. Amazon replaced it instantly so not a big deal. I don’t use it TBH because my daily driver is an HP35s which is waaaay more powerful.This line of calculators is standard issue in UK schools at the moment and you don’t get any complaints.

author: Shock
author_rank: Super Contributor
timestamp: April 13, 2019, 10:44:55 am
content: The best Casio keys in my opinion were the hard plastic ones of the 80s. The newer models always seem to have a couple of design flaws that affect usability.

author: voltsandjolts
author_rank: Unknown
timestamp: April 13, 2019, 11:38:19 am
content: TI-85 eats Casio toys for lunch

author: bd139
author_rank: Super Contributor
timestamp: April 13, 2019, 11:41:36 am
content: Quote from: voltsandjolts on April 13, 2019, 11:38:19 amHorrid screen. Fixed in TI-86

author: gildasd
author_rank: Frequent Contributor
timestamp: April 13, 2019, 12:01:19 pm
content: Quote from: bd139 on April 13, 2019, 11:41:36 amCough, Ti-89/92, cough.

author: bd139
author_rank: Super Contributor
timestamp: April 13, 2019, 12:18:35 pm
content: If we’re going down that route, HP50G

author: Mortymore
author_rank: Frequent Contributor
timestamp: April 13, 2019, 12:26:09 pm
content: Quote from: gildasd on April 13, 2019, 12:01:19 pmCasio FX-991EX ClassWiz is aScientific Calculatornot a graphing calculator.Like multimeters and oscilloscopes, both measure voltage, but you wouldn't mixed em up, right?

author: 2N3055
author_rank: Super Contributor
timestamp: April 13, 2019, 12:38:48 pm
content: Quote from: Mortymore on April 13, 2019, 12:26:09 pmAnd also Casio is 20 USD. Best price performance there is.You bet your ass Porsche is nicer than Clio Sport. But in reality they are equally fast point A to point B. Road conditions, traffic and average persons driving skills will take care of that.

author: bd139
author_rank: Super Contributor
timestamp: April 13, 2019, 12:41:11 pm
content: Quote from: Mortymore on April 13, 2019, 12:26:09 pm

author: Mortymore
author_rank: Frequent Contributor
timestamp: April 13, 2019, 01:04:44 pm
content: Very funny of you, but I'm sure you know what I mean.PS: TO-126... TO-3 understood

author: rsjsouza
author_rank: Super Contributor
timestamp: April 13, 2019, 01:58:44 pm
content: Quote from: Shock on April 13, 2019, 10:44:55 amI have a few late 1970s and early 1980s Casios with the same buttons and their resistive membrane becomes very brittle and breaks, turning the calculator into a brick. I personally don't see many being sold in the used market anymore when compared to TIs and HPs, perhaps suggesting these models didn't age well.Quote from: 2N3055 on April 13, 2019, 12:38:48 pmAt this level of scientific calculator, I find them all pretty much the same, both in display and in tactile fell - the HP35S, which I find well above average in terms of keypress feel and quality, is my daily driver. However I don't use it for scientific but base conversion insteadI disliked the low contrast display of my former TI89 Platinum, even when compared to the graphical HP48SX/GX. The Casios and HPs are much better.

author: 2N3055
author_rank: Super Contributor
timestamp: April 13, 2019, 02:30:32 pm
content: My FX-61 is still going strong. One thing that shows time passage is plastic etui. Calculator itself not really. It's 198-something vintage so quite old.

author: Technobabble_
author_rank: Regular Contributor
timestamp: April 13, 2019, 04:29:28 pm
content: QuoteAh well. My fx-9750G-II isn't winning any rewards, but at least the button feel is acceptable.Is there a new scientific calculator with non-mushy keys that anyone recommends? My TI-30x is great, but I don't like the single line display. Anybody can comment on the keys for the TI-36X pro?

author: bd139
author_rank: Super Contributor
timestamp: April 13, 2019, 06:50:42 pm
content: HP35sAnd yes it has a normal entry mode for lamers

author: rrinker
author_rank: Super Contributor
timestamp: April 18, 2019, 03:48:15 pm
content: My favorite is still my Radio Shack rebrand of the Casio FX-451m, with the scientific and engineering constants built in plus all the programming features like base conversion and logical operations, it was absolutely perfect for what I did. I used that the last 2 or 3 years of college, and then I kept using it as my go-to calculator right up until somewhere around 1994 when my older son who was about 3 at the time managed to get hold of it and 'hid' it - inside a bedside lamp with a 100 watt bulb in it. Melted right through the foldable side and destroyed all the keys on that side.

author: Specmaster
author_rank: Super Contributor
timestamp: April 18, 2019, 06:55:26 pm
content: Out of all the calculators I own, here is my outstanding favourite, Commodore SR4912 which I used during my college days and is still in daily use and working perfectly after 54 years, never failed once during that or had a battery leak, buttons are nicely sprung and silent, not at all clunky some are especially the HP ones of that era and it uses a 9v battery whereas the HP ones and many other use AA cells and all the HP AA powered calculators I have and know of have all at some point suffered from leaking batteries.

author: rrinker
author_rank: Super Contributor
timestamp: April 19, 2019, 02:51:30 pm
content: I did not think I was actually very OCD at all, but those tilted buttons...ack!

author: rsjsouza
author_rank: Super Contributor
timestamp: April 19, 2019, 05:04:17 pm
content: Quote from: rrinker on April 19, 2019, 02:51:30 pmFunny you mentioned that... That put me off as well.

author: Specmaster
author_rank: Super Contributor
timestamp: April 19, 2019, 05:48:40 pm
content: Quote from: rrinker on April 19, 2019, 02:51:30 pmHaha, well to be fair it's had about 46 years of wear and tear and its still going strong (I was wrong about it being 54 years old) so I don't think it doing bad at all in that case.

author: Mortymore
author_rank: Frequent Contributor
timestamp: April 19, 2019, 08:09:15 pm
content: Quote from: Specmaster on April 19, 2019, 05:48:40 pmI think the first pocket calculator hit the market around 1971.EDIT:Commodore SR4912