Things to improve on the hardware

If you're having problems with the hardware of a DM41X or DM42, post about them here.
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lpoujoulat
Posts: 6
Joined: Thu Jan 04, 2018 12:04 am
Location: France

Things to improve on the hardware

Post by lpoujoulat »

Hello all,

I want first to tell how I like my DM42 (S/N 222). It's now my primary calculator. After some months using it, I just want to share my thoughts about some things that should/could be improved to make it perfect on the hardware side. These are by decreasing importance:
- The keyboard (see other threads about this),
- The high light reflection on the screen,
- The USB connector that is a bit too inward and don't work with all cables,
- The assembly of the two plates is a bit "creaky" on the middle,

Will a new release of the hardware be done in the future ? If the DM43s comes to live one day, it would be good to have this fixed to get the best of the calculators.

Regards
Laurent
HP67, HP11C, HP16C, HP28S, HP50G, DM42 #222
mcc
Posts: 277
Joined: Fri Jun 23, 2017 5:10 am

Re: Things to improve on the hardware

Post by mcc »

Hi,

I would add

- a small capacitor in parallel to the battery

to avoid program loss in case of dropping the calculator on a hard surface
accidentally. It happens to me.
These drops disconnect the battery for a very short time from one of its
contacts and without power the RAM is cleared (and maybe the CPU is reseted ).
he capacitor would provide energy in that very moment.

Cheers
Meino
DM 42 - SN: 00373, Firmware release v.:3.22. / DMCP 3.24. as compiled by SwissMicros
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Over_score
Posts: 160
Joined: Fri May 05, 2017 9:37 pm
Location: France

Re: Things to improve on the hardware

Post by Over_score »

lpoujoulat wrote:
Sun Jul 08, 2018 4:59 pm
- The keyboard (see other threads about this)
+1 (a very big +1 :mrgreen: )
mcc wrote:
Mon Jul 09, 2018 3:34 am
- a small capacitor in parallel to the battery
+1

Cheers
Martin
DM42 SN00284 & SN03835 running C47, HP34C, HP41CV, HP42S, HP35s, WP34S, HP Prime
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pica
Posts: 70
Joined: Fri Mar 30, 2018 11:36 am
Location: Eswatini

Re: Things to improve on the hardware

Post by pica »

On the issue of screen glare. By chance I came across a matte screen protector for a kindle ereader. Cut to size it makes a good improvement to the readability of the screen.
HP50G HP35s Free42 DM42.
Testing WP43S, C43.
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Jaymos
Posts: 1635
Joined: Sun Nov 04, 2018 7:03 pm
Location: Cape Town

Re: Things to improve on the hardware

Post by Jaymos »

Hi Pica,

Is this the kind of screen you refer to?

https://www.amazon.co.uk/dp/B07JMRHNLQ/ ... OCbNRNCWDV

Regards
pica wrote:
Mon Feb 11, 2019 5:56 pm
On the issue of screen glare. By chance I came across a matte screen protector for a kindle ereader. Cut to size it makes a good improvement to the readability of the screen.
Jaco Mostert
Elec Eng, South Africa
https://47calc.com C47 (s/n 03818 & 06199), WP43 (0015). In box: HP42S, HP32Sii, WP34S&C, HP28C, HP35s, EL-506P, EL-W506, PB700; ex: FX702P, 11C, HP67 & HP85; iOS: 42s Byron, Free42+, WP31S/34S, HCalc.
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pica
Posts: 70
Joined: Fri Mar 30, 2018 11:36 am
Location: Eswatini

Re: Things to improve on the hardware

Post by pica »

Yes, it was that kind of thing, although not that exact brand.
HP50G HP35s Free42 DM42.
Testing WP43S, C43.
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