SwissMicros Calculator Forum

My ENTER button has unacceptable behaviour - pressed close to the right edge acts like the rest of the buttons; close to the left edge - a lot quieter and weak click, and in the middle - no click at all. Registers in every case, which makes things worse, no way to tell the result unless checked in the display. I can't notice any difference in the respond when pressing both domes while calculator is disassembled. Suggestions made earlier here to play with the wide internal screws or readjusting position of the whole dome board don't look serious and reported results (fixing) - imaginary. When I opened it for the first time, the screw closer to the ENTER was laying there free, completely out of its hole, how could I fix problem by releasing it?

I'm sorry for this. Finally we nailed the problem with the ENTER button.
The unequal tactile feedback is caused by the upwards bent ABS housing.
Once the calculator is taken apart and warmed up a little, it can be bent back which should solve the issue.
Please give it a try. Otherwise you can send it back to me and I'll fix it.

Glad it's an easy fix. Would it be possible for there to be a quick video tutorial so we know what we to bend and how much please?

Thanks Michael, hope this solves the problem. I join the previous poster about video tutorial how this is to be done.
Cheers.

keithdalby wrote: ↑

Thu Apr 12, 2018 1:16 pm

Would it be possible for there to be a quick video tutorial so we know what we to bend and how much please?

I'll try making a video this weekend...

Hi Michael,

thanks a lot for the investigation and the solution! We will ENTER an new era
of ENTERtainment (just playing with words, there is no hidden something
"between the lines" )

A question:
When opening the back and closing the back again, there is always a certain amount
of pressure needed to close the back completly.
So I think (read: really don't know for sure), that the back a slightly to short or the
radius of the upper end of the back does not fit exactly the radius of the upper end
of its counterpart.
When "unbending"/"Stretching" (word?) the ABS part it will become a little longer.

Would this bend the ABS again after a while of usage?

Cheers!
Meino

I'm glad you got to the bottom of it. Did you need a fiberscope to see what was going on?

I may risk dismantling my calculator one more time to fix it once the video has been posted. We have a hot-air gun at work somewhere!

Well, to answer my own question, when I took out the circuit board, all the little metal domes responded with a very positive click when pushed with a matchstick. This led me to think that the keyboard might be too close to the circuit board. Loosening the two big screws helped, but I am not willing to carry around a calculator with loose screws inside. The solution was therefore to put two narrow strips of photocopy paper (3mm by 40mm, folded in half longways) between the keyboard and the circuit board right at the edges of the boards and then reassemble. All the keys work just fine now.

Wow, good catch. Looking at my DM42, I suspect this bend is what I've been calling the "bulge caused by the beeper". Looking forward to the video.

Michael wrote: ↑

Thu Apr 12, 2018 4:01 pm

keithdalby wrote: ↑

Thu Apr 12, 2018 1:16 pm

Would it be possible for there to be a quick video tutorial so we know what we to bend and how much please?

I'll try making a video this weekend...

Did you get a video made? My Enter key is reliable only if I screw in the large-headed screws just enough to catch the threads without tightening them at all. If I tighten them even one turn, the left side of the enter key registers but there's no click. I'd like to be able to screw them all the way down and still have my keys work.