My order of RevC boards and enclosures has come in the mail.

This is the first time that I’ve added tiny spark gaps to all exposed board inputs. They turned out well (no shorts).

For the enclosure of RevC, I’ve tried out Seeedstudio’s new laser engraving service.

I’m sure it wasn’t easy to burn the small print of the calculator’s keyboard lables into the clear acrylic cover.
The people at Seeedstudio were really nice and experimented with my design to improve
readability. In the end they sent me two versions of the engraved front covers. One has a filled font (this is basically
what my original design looked like):

The other variation uses an outlined font.

I think they both turned out well.

Now I need to come up with a good way to color the engraved labeling. Maybe I should have ordered black PCBs instead of white ones.