The first RevC calculator nas been built. I still need to do something to improve the contrast of the keypad labels.
RevC comes with lasercut acrylic spacers.
I was out of 1uF SMD capacitors, but the PCB has enough room for through hole components.
During the PCB assembly I’ve discoverd one design bug: LED1 and LED2 have been flipped the wrong way around in the
schemactics. Therefore the cathode markings
on the silkscreen are on the wrong side. The design files have been corrected in the current git commit.
There had also been a mistake in the assembly plan:
resistor labels R9 and R10 had been swapped (also fixed in the current commit).
A further pitfall is the orientation of resistors R11 and R12. The assembly plan
didn’t give any hint that they need to be mounted horizontally, whereas all neighboring components ate aligned vertically.