A few suggestions to improve the hardware DM41.
Posted: Sun Oct 31, 2021 6:24 pm
Just a few suggestions to improve the hardware of the swissmicros DM41.
The plastic between the LCD and the transparent keypad window is not necessary, it also creates problems by sticking to the LCD and giving a water print underneath due to sticking. I have removed it.
If you press too hard on the keyboard area on the battery, a short circuit can occur sometimes and the memory is erased and I think it is due to a not very good soldering of the battery box with the PCB when PCB is hard pressed.
In any case, the anti-short circuit sticker seems unnecessary since titanium is a very poor conductor and I tried to create a short between the + pole and the titanium housing without plastic sticker over battery and it was impossible produce a MEMORY CLEARED but touching with copper cable pole + and the house of screws produce a MEMORY CLEARED.
I think that the battery box and the pressure and deformation of the PCB in that area should be studied to prevent resets.
Test it without titanium housing and deform gently a little the PCB and in certain cases ... reset.
I have solved these problems with a good cleaning of the battery box and putting a conductive metal type washer between the + pole of the battery and the battery case so that there is no gap and the battery is firmly seated no matter how much pressure is applied on it from the keyboard.
Improve the soldering of the + pole with the PCB and the internal contact of the battery on the negative pole since it looks dirty even after cleaning it and does not see gold or silver.
Less glue near the domes of the keys since pressing hard sometimes they stay stuck and you have to detach the keyboard and stick it again to release them.Now is working fine to me after two times remove keyboard and put again.
Just 1mm or 1,5mm of glue grid around the keys I think would improve tactile feedback and prevent keyboard issues and noise when the key is lifted and "dragged" on the keyboard giving an unpleasant adhesive noise.
The screws 0,5mm or 1mm less long to prevent push keyboard up.
Write on the back of DM41 RESET hole to not confuse the two holes RESET ... PGM.
After all a great product and idea that can be better with some improvements in hardware.
The plastic between the LCD and the transparent keypad window is not necessary, it also creates problems by sticking to the LCD and giving a water print underneath due to sticking. I have removed it.
If you press too hard on the keyboard area on the battery, a short circuit can occur sometimes and the memory is erased and I think it is due to a not very good soldering of the battery box with the PCB when PCB is hard pressed.
In any case, the anti-short circuit sticker seems unnecessary since titanium is a very poor conductor and I tried to create a short between the + pole and the titanium housing without plastic sticker over battery and it was impossible produce a MEMORY CLEARED but touching with copper cable pole + and the house of screws produce a MEMORY CLEARED.
I think that the battery box and the pressure and deformation of the PCB in that area should be studied to prevent resets.
Test it without titanium housing and deform gently a little the PCB and in certain cases ... reset.
I have solved these problems with a good cleaning of the battery box and putting a conductive metal type washer between the + pole of the battery and the battery case so that there is no gap and the battery is firmly seated no matter how much pressure is applied on it from the keyboard.
Improve the soldering of the + pole with the PCB and the internal contact of the battery on the negative pole since it looks dirty even after cleaning it and does not see gold or silver.
Less glue near the domes of the keys since pressing hard sometimes they stay stuck and you have to detach the keyboard and stick it again to release them.Now is working fine to me after two times remove keyboard and put again.
Just 1mm or 1,5mm of glue grid around the keys I think would improve tactile feedback and prevent keyboard issues and noise when the key is lifted and "dragged" on the keyboard giving an unpleasant adhesive noise.
The screws 0,5mm or 1mm less long to prevent push keyboard up.
Write on the back of DM41 RESET hole to not confuse the two holes RESET ... PGM.
After all a great product and idea that can be better with some improvements in hardware.