Monday, June 26, 2017

2 Pack

2 Key PCB with top and bottom plates

Tiny 2 Key macropad, PCB and case parts combined. The PCB is similar to the previous 2 Key PCB, the main change is the rotation of the switches. This puts the switch pins farther away from the USB connector on the Pro Micro so that it is less likely to make contact and short out. The pinout is the same, switches are connected to pins 2 and 3. The LEDs are connected to pins 9 and 10.

In the current version the USB port is recessed too far for some larger USB cable connectors. Planning on a version with a small cutout on the bottom plate to accommodate the larger connectors. It will also allow for shorter standoffs.

There is printing on the top sides of the plate pieces. The bottoms are blank, it can be built with either side facing out. Other than switches, the only other parts are 2 LEDs and the 2 resistors for them.

The pieces snap apart. The edges need to be sanded down. I used 220 grit wet/dry sandpaper on a flat surface. I wet sanded all four sides smooth. I also sanded off the solder mask on the plate pieces.

4 different builds.
  • Gateron Clear/permanent pin headers
  • Invyr Panda/permanent pin headers
  • Gateron Red/low profile socket
  • Kailh Speed Bronze/Holtites and full height socket
End view of the four. Three have 10mm spacers. The one with the full height socket has 12mm spacers.

Side view. Thin laptop style screws were used. These are so small the only way to secure them in place would be double stick tape. I use 3M Command strips which are removable.

Invyr Panda switches with integrated sockets. LEDs are installed under the switch and fit in the slots. The Panda sockets do not fit all MX style switches.

Holtite sockets fit properly without soldering. They press fit as they were designed.

Switches and LEDs inserted into sockets. You can see the red brand marking on the PCB. Normally not seen when covered with solder mask. From EasyEDA.com I have seen several different brand markings. Some are darker than others. This one is the darkest and most visible.