Author Topic: EEVblog #1159 - World's Most Precise Pocket Calculator  (Read 7199 times)

0 Members and 1 Guest are viewing this topic.

Online EEVblog

  • Administrator
  • *****
  • Posts: 29680
  • Country: au
    • EEVblog
EEVblog #1159 - World's Most Precise Pocket Calculator
« on: December 17, 2018, 12:58:33 pm »
One item mailbag!
A look at the Swissmicro DM42, the world's most precise pocket calculator.
A clone and improvement of the famous HP42S, with open source firmware based on the Free42 platform.

https://www.swissmicros.com/dm42.php
http://thomasokken.com/free42/


 
The following users thanked this post: SeanB, imo, inOr

Offline dr.diesel

  • Super Contributor
  • ***
  • Posts: 2123
  • Country: us
  • Cramming the magic smoke back in...
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #1 on: December 17, 2018, 01:39:50 pm »
That is quite nice!  Is the display cover glass or plastic?

Offline imo

  • Super Contributor
  • ***
  • Posts: 1757
  • Country: 00
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #2 on: December 17, 2018, 05:27:58 pm »
I think the "most precise pocket calculator" is the WP-34S.
https://sourceforge.net/projects/wp34s/
It uses DecNumber library with up to 50 decimal places precision.
« Last Edit: December 17, 2018, 05:32:15 pm by imo »
 

Online bsudbrink

  • Frequent Contributor
  • **
  • Posts: 341
  • Country: us
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #3 on: December 17, 2018, 09:19:13 pm »
Just so you know, YouTube has this video marked as "unlisted".  I'm not sure what this means, but I don't see it on my YouTube account subscription page.
 

Offline darik

  • Contributor
  • Posts: 46
  • Country: ca
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #4 on: December 17, 2018, 11:53:41 pm »
To show the full precision, use shift-decimal (SHOW).
 

Offline Dubbie

  • Supporter
  • ****
  • Posts: 987
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #5 on: December 18, 2018, 12:56:26 am »
I have this calculator, the only issue I have with it is that the button feel is not as nice as it could be. It is my daily driver at work though.
 

Online EEVblog

  • Administrator
  • *****
  • Posts: 29680
  • Country: au
    • EEVblog
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #6 on: December 18, 2018, 02:13:37 am »
To show the full precision, use shift-decimal (SHOW).

Ah, that works, but unfortunately does not show up long enough to read it!
UPDATE: You have to continue to hold down the button to keep it showing

« Last Edit: December 18, 2018, 02:15:55 am by EEVblog »
 
The following users thanked this post: darik

Online EEVblog

  • Administrator
  • *****
  • Posts: 29680
  • Country: au
    • EEVblog
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #7 on: December 18, 2018, 02:17:54 am »
Actual Calculator Forensics result:
 
The following users thanked this post: darik

Offline imo

  • Super Contributor
  • ***
  • Posts: 1757
  • Country: 00
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #8 on: December 18, 2018, 03:35:20 am »
It seems Dave's buttons died :)
A big pain all these recent attempts to mimic the original HP-clicky buttons. The WP-34s (HP-30b hw) I own still clicks, but mostly because I stopped using it in order to save the buttons :)
The thin plastic pins (about 2.5mm long 1mm dia) pushing onto the metal dome usually bend/broke when pushing a little harder.

The DM-42 does not use such long pins, it may last a little bit longer. Not sure you get such HP-feel with it, however.
And my HP-25 and HP-48GX is still clicky..
« Last Edit: December 18, 2018, 03:39:08 am by imo »
 

Offline BrianHG

  • Super Contributor
  • ***
  • Posts: 2959
  • Country: ca
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #9 on: December 18, 2018, 03:52:42 am »
Holly cow Dave!  Your enthusiasm shines through to the moon.  :-+
__________
BrianHG.
 

Offline inOr

  • Newbie
  • Posts: 4
  • Country: us
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #10 on: December 18, 2018, 05:41:53 am »
Once I tried to write a DEC Fortran program to solve a quadratic the high school way, the exact formula you know -b+/- sqrt(b^2 ...., I got a ridiculous answer, so I tried a numeric routine from the DEC collection and wow was that wrong!  So I programmed my own numeric routine and that worked.  Meanwhile, I used my HP xx scientific calculator.  I can't remember the precision, but the answer was bang-on.  They do have their uses...
 

Offline johnlsenchak

  • Frequent Contributor
  • **
  • Posts: 280
  • Country: us
  • js@antihotmail.com
    • paypal.me/johnsenchak
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #11 on: December 18, 2018, 05:49:01 am »

Years ago,   I had a  real nice  programmable HP scientific    calculator    where I  wrote a programs  to  calculate  A/C   circuits when  it came to inductors and  capacitors   .
John Senchak "Daytona  Beach  Florida "
 jls (at)  antihotmail.com   http://www.antihotmail.com
https://www.facebook.com/john.senchak.1
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 9979
  • Country: 00
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #12 on: December 18, 2018, 11:55:17 am »
To show the full precision, use shift-decimal (SHOW).
I was shouting that at the screen while the video was running.  :popcorn:

Ah, that works, but unfortunately does not show up long enough to read it!
UPDATE: You have to continue to hold down the button to keep it showing

How many does it show? 12 digits?
 

Offline NivagSwerdna

  • Super Contributor
  • ***
  • Posts: 1759
  • Country: gb
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #13 on: December 18, 2018, 01:38:24 pm »
Nice.  I have a poor man's version WP 34S .  I know 42S is super popular with the fanboys but IMHO it's a bit hard to live with unless you use it every day since the functions are hidden away... I think I prefer the ones that just have lots of functions on the buttons...

I also have a HP35S which is a nice compromise and not bad for a modern device.

 

Offline Gribo

  • Frequent Contributor
  • **
  • Posts: 411
  • Country: ca
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #14 on: December 18, 2018, 04:07:32 pm »
Does anyone knows who manufactures the display? I have been looking for an E-paper display with fast response time for quite a while.
 

Offline imo

  • Super Contributor
  • ***
  • Posts: 1757
  • Country: 00
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #15 on: December 18, 2018, 06:28:00 pm »
LS027B7DH01 from Sharp Microelectronics..
 

Offline pauli

  • Newbie
  • Posts: 1
  • Country: au
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #16 on: December 18, 2018, 09:33:30 pm »
It's off by one in the last digit :)

Refer: http://www.hpmuseum.org/forum/archive/index.php?thread-10355.html


Pauli
 

Online rsjsouza

  • Super Contributor
  • ***
  • Posts: 3393
  • Country: us
  • Eternally curious
    • Vbe - vídeo blog eletrônico
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #17 on: December 18, 2018, 09:44:04 pm »
I also have a HP35S which is a nice compromise and not bad for a modern device.
:-+ :-+ :-+
Although a bit more cumbersome to do base conversion when compared to my 48GX, the 35S is quite nice. (I leave my 48GX at home as I am afraid it will be stolen).
Vbe - vídeo blog eletrônico http://videos.vbeletronico.com

Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 

Online EEVblog

  • Administrator
  • *****
  • Posts: 29680
  • Country: au
    • EEVblog
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #18 on: December 18, 2018, 09:44:25 pm »
It's off by one in the last digit :)
Refer: http://www.hpmuseum.org/forum/archive/index.php?thread-10355.html
Pauli

Hey Pauli, long time no see, welcome to the forum!
 

Offline Spirit532

  • Frequent Contributor
  • **
  • Posts: 407
  • Country: by
    • My website
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #19 on: December 19, 2018, 01:52:00 am »
I believe the display is a Sharp Memory LCD with the model number LS027B7DH01
It's a ridiculously low retention power graphical LCD, but it comes at a hefty price premium.
 

Offline 3roomlab

  • Frequent Contributor
  • **
  • Posts: 938
  • Country: 00
  • can you tell me how to cal sesame street meter?
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #20 on: December 19, 2018, 10:18:21 pm »
nothing against real physical calculators. but for those who have tablets old or new, install one of those scientific calculator apps on it (there are hundreds in google app store, some are better, I am using one which appears to be done by a viet dev, they basically copied the entire sci-calc into an app. some includes programming features.), there is nothing like a portable scientific calc with a 10" screen and buttons the size of a thumb. I repeat, buttons with the size of a thumb.

there is nothing like using thumbs to press them, the satisfaction (or fun). and there is no printed words to rub off like casios.
« Last Edit: December 19, 2018, 10:44:33 pm by 3roomlab »
spheres of influence, example linustechtips. can you feel the brainwashing? showing off equipment, etc. were you swayed and baited? with immense popularity (and social "titles"), can you afford to disagree?
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 9979
  • Country: 00
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #21 on: December 19, 2018, 10:36:19 pm »
there is nothing like a portable scientific calc with a 10" screen and buttons the size of a thumb. I repeat, buttons with the size of a thumb.

 :wtf:

Some of us still have good eyesight and a bit of hand-eye coordination.
 

Offline floobydust

  • Super Contributor
  • ***
  • Posts: 2880
  • Country: ca
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #22 on: December 19, 2018, 10:39:18 pm »
All these app-based calculators still suck compared to old tech.
I have a Sharp EL5103-S that rounds results to engineering units (milli, micro, nano, kilo etc.).
It's great instead for EE work, instead of converting exponents.

The pocket calc speed test I did was always 69! (69 factorial), I wonder how long that takes on this calculator. TI-30 LED was 2 seconds lol.
 

Online rsjsouza

  • Super Contributor
  • ***
  • Posts: 3393
  • Country: us
  • Eternally curious
    • Vbe - vídeo blog eletrônico
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #23 on: December 20, 2018, 03:27:50 am »
there is nothing like using thumbs to press them, the satisfaction (or fun). and there is no printed words to rub off like casios.
My old Kindle Fire HD still has a beautifully coded HP-12C in voyager style. Although its size and functionality are quite nice, pressing virtual buttons is not the same at all. YMMV, though.

The pocket calc speed test I did was always 69! (69 factorial), I wonder how long that takes on this calculator. TI-30 LED was 2 seconds lol.
Heh, I did the same. My old Casio fx-39 took about 10 seconds! My dad's TI-59 did not have a built-in factorial function, and the best program I could make at the time took somewhere between 10 and 15 seconds.
Vbe - vídeo blog eletrônico http://videos.vbeletronico.com

Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 9979
  • Country: 00
Re: EEVblog #1159 - World's Most Precise Pocket Calculator
« Reply #24 on: December 20, 2018, 07:49:09 am »
My old Kindle Fire HD still has a beautifully coded HP-12C in voyager style. Although its size and functionality are quite nice, pressing virtual buttons is not the same at all. YMMV, though.

12C? Ew! That's a calculator for bankers.

HP does the 15C (scientific) for Android:

https://play.google.com/store/apps/details?id=com.hp.hp15c15&hl=en_US

(it turns into an RPN  four-banger when you rotate to portrait mode, too)
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf