After extensive use: The keyboard

Discussion about the new DM41X calculator
isene
Posts: 44
Joined: Sat Jul 22, 2017 2:02 am

After extensive use: The keyboard

Post by isene »

I have now put my DM41X (sn 088) to extensive use the past couple of months. The last update fixed my HEPAX issues completely. Thanks for that :-)

My only two concerns now is the lack of HP-IL (or similar programatic external interface - like possibility of real-time bidirectional signals over USB that can be controlled somehow by a FOCAL program). The other is the keyboard.

For the DM41X to be a calculator I can use in the future, there is one single critical requirement for me:

There should be no way a keystroke will not register when I press a key.

As it is now, about one out of 10-15 keystrokes do not register (regardless of which key - there are no specific "faulty keys" on my keyboard... this is a real keyboard issue, it covers all the keys). This is the most pressing issue to be fixed - this is why I still prefer my HP-41CL.
Dan Simpson
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Re: After extensive use: The keyboard

Post by Dan Simpson »

I have to agree. I have had a DM42 for about one year and now a DM41X Beta.
I really want to like them but I have the same keystroke issues on both of them that you are describing.
I can't trust them without watching the screen during each key press.

I have just built a second 41CL so I have a backup. I am just used to the feel and reliability of the original keyboard.
My Spirit animal is a Basset Hound.
My Collection: HP-55, HP-67 (Teenix Mod), HP-15C, HP-16C, HP-41CV, HP-41CX, SY41-CL (x2), DM41X (Beta), DM42, HP-42S, HP-48G, HP-71B (x2), HP-75C, HP-150.
jonmoore
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Re: After extensive use: The keyboard

Post by jonmoore »

I recently took my 41x apart to make the keyboard more pliant and to my horror discovered that dusty particulate gets into the innards of the DM... hardware far too easily. The good news is that the DM... hardware has been designed to be taken apart so that customers can augment or generally maintain their purchase so it's a relatively easy task. My unit was also suffering particulate trapped between the front glass and the LCD but yet again it's an easy fix (with the aid of a sucker to remove the glass part).

If you are taking the back off of you DM... hardware for maintenance tasks the only key thing to be careful about is the connector for the LCD, which has a band which first has to be removed before you can safely detach the LCD from the PCB (it's a delicate part so be sure to be gentle). Once you've done that, a quick once over with some isopropyl alcohol should fix any dodgy contacts. The combination of particulate and grease is the thing that seems to have caused occasional missed key entries in my case. After cleaning and loosening of the key mechanism my 41x is a delight to use and I've not had a missed key since I performed the service on Thursday.
Geoff Quickfall
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Re: After extensive use: The keyboard

Post by Geoff Quickfall »

Repeat, see below :shock: :o
Last edited by Geoff Quickfall on Mon Jun 01, 2020 3:59 am, edited 3 times in total.
Geoff Quickfall
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Re: After extensive use: The keyboard

Post by Geoff Quickfall »

How’s the 41 cl working Geir!

Like you, the need for a functional HPIL is a requirement for me. HPIL on the flight deck, not required; HPIL in the lab, required.

Therefore DM41x on the flight deck and 41CL in the lab 8-)

Cheers, Geoff
isene
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Joined: Sat Jul 22, 2017 2:02 am

Re: After extensive use: The keyboard

Post by isene »

The 41CL is working great - it's my all time favourite calc.

As for cleaning the keyboard, etc - I have seen no deterioration to the keystrokes.

After a couple of weeks of use it went from missing around every 10th keystroke to much better. I went on a mission to learn to press the keys harder - not trusting the "click", but pressing beyond that. This got the miss-rate down to about 1%. But I just can't keep up with the hard-press-the-keys-beyond-the-click-routine. Now I'm missing between 7%-10% of the key presses when I key in large programs. And this is unbearable.
jonmoore
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Re: After extensive use: The keyboard

Post by jonmoore »

Back on the subject of servicing the 41x to get the best out of the device, I've come to think of it in a very similar vein to maintaining my 1966 Lambretta (maintaining a classic sports car is a tad beyond my pocket, not to say abilities!). It's needs TLC on a regular basis, but when you make that extra effort your rewards are plentiful.

I suppose when it comes to limited run, highly engineered things, 'owner TLC' is sometimes the cost of entry. And that applies as much to maintaining a classic 41 or retrofitted 41cl as it does to a 41x, never mind a classic Italian scooter.
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pcscote
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Re: After extensive use: The keyboard

Post by pcscote »

isene wrote:
Sun May 31, 2020 3:28 pm
There should be no way a keystroke will not register when I press a key.
+41 times

I used it seriously for some times but at some point I gave up.
Way too many missed keys, I had to always look at the screen watching for missed keys.
Program entry speed was awful, I had to double or triple check every lines.
The firmware is coming along nicely and the improvement made to the base system is really interesting
but with its main user interface problematic (keyboard) my user experience was below par, at least for me.

Sylvain
[DM1x/DM1xL/DM41/DM41L/DM41X/DM42]
isene
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Joined: Sat Jul 22, 2017 2:02 am

Re: After extensive use: The keyboard

Post by isene »

I will narrow this down to:

The click of a key must always register the key pressed.
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Walter
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Re: After extensive use: The keyboard

Post by Walter »

isene wrote:
Wed Jun 03, 2020 2:22 pm
I will narrow this down to:

The click of a key must always register the key pressed.
Aye, aye, Sir. Let's hope the hardware department is listening (remember: this is the department with zero tolerance :roll: ). 8-)
DM42 SN: 00041 Beta
WP 43S running on this device

HP-35, HP-45, ..., HP-50, WP 34S, WP 31S, DM16L
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