DM42 early units vs. current?

[Antonius]

If you browse through the forum posts of the DM42, it seems that the keyboard is the biggest concern. It is not a case of a 'bad workman quarrels with his tools'. If I cannot trust the tool I am working with, it will be replaced with some other tool. At the end it becomes a bad investment and you resent the brand. Programming errors due to bad keyboard design is worse than your own programming errors.
I am contemplating either the DM15L or DM42, but this keyboard issue concerns me and i think I will rather go with the DM15L and get the DM42 in its third iteration.

[Steve Simpkin]

Any DM42s ordered since Oct of 2020 should have the new improved keyboard which is much better than the earlier versions.

See:
https://www.hpmuseum.org/forum/thread-15...#pid137510

[revwillie]

(09-02-2021 07:47 PM)Steve Simpkin Wrote:  Any DM42s ordered since Oct of 2020 should have the new improved keyboard which is much better than the earlier versions.

my memory might not be totally correct, but was there discussion about a keyboard upgrade that could be purchased for the original beta units?

[Massimo Gnerucci]

(09-24-2021 02:22 PM)revwillie Wrote:  

(09-02-2021 07:47 PM)Steve Simpkin Wrote:  Any DM42s ordered since Oct of 2020 should have the new improved keyboard which is much better than the earlier versions.

my memory might not be totally correct, but was there discussion about a keyboard upgrade that could be purchased for the original beta units?

N/A (yet?)

[RMollov]

(09-24-2021 02:22 PM)revwillie Wrote:  

(09-02-2021 07:47 PM)Steve Simpkin Wrote:  Any DM42s ordered since Oct of 2020 should have the new improved keyboard which is much better than the earlier versions.

my memory might not be totally correct, but was there discussion about a keyboard upgrade that could be purchased for the original beta units?

When and if this becomes available, I'd purchase one straight away - and I will not buy another calculator just for the (slightly improved) keyboard. I've got DM41X with the "newer" keyboard and I am not impressed with it too...

I do understand HP41C's keyboard from abt 40 years ago is unachievable target these days despite technology advance

[Hlib]

The best keyboard I know well is the usual cheap CASIO graphic calculators. In afx-2.0, I studied this in detail. Everything is perfectly implemented there at the firmware level in the processor. All clicks first go to memory and are analyzed by statistical methods. Then, as in a stack, codes for each key are sequentially issued. Even with very bad rubber, you can work quite satisfactorily, not to mention a high-quality keyboard. I have always been surprised by the hp-50g`s ability to skip keystrokes, even in the emulator on a smartphone, this is constantly observed. This is probably a very difficult task, even if SwissMicros still cannot solve it.

[DavidM]

(09-30-2021 04:39 PM)Hlib Wrote:  I have always been surprised by the hp-50g`s ability to skip keystrokes, even in the emulator on a smartphone, this is constantly observed.

If you haven't already, you may want to try setting a new value for keybounce timing for your 50g. The default value of 1138 is a bit excessive for my taste; I use a value of 600 and find it works much better for me.

Try:

Code:

600 →KEYTIME

That may provide a better experience for you as well.

[Hlib]

@ DavidM
Hi David! If I remember correctly, you made a wonderful application ListExt for the hp-50g. In hp-50g, I have known the KEYTIME➝ function for a long time, but this does not eliminate the defect either in the real calculator (I had three of them) or in the emulator. The key click always functions, but no action occurs. Approximately once per 50 ± 25 taps on average. Perhaps I had calculators from a defective series.

[Uli]

Have you compared the design (engineering) of the keyboard of the 41c with the DM4x? How can we hope that the function is similar?

I think our common problem is that there are no new 41c are available.

I care for my 41c’s and hope that they will work for the rest of my life.
(I used my DM4x to test them, afterwards I stopped playing with them)

To buy a new used 41c is not an option in these days (in Germany). The prices at e*y are unbelievable…… Same effect you can see at LEICA M.