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Protozoa P.01 Build Guide

Welcome to the P.01 Build Guide.


This guide will show you have to assemble your PCB if you bought the through-hole kit as well as assemble the case itself. If you purchased the "Ultra PCB" feel free to skip ahead to the case assembly section.

The P.01 uses the Mysterium open-source PCB designed by coseyfannitutti from

A majority of the through Hole PCB build guide is pulled directly from build guide and for the most part it's the same. However, we have made a few small changes to the PCB to make it unique to Protozoa.


Warning: Soldering can cause harm to yourself and others. Please review this Safety Guide before beginning. You're soldering at your own risk.


Let's get started.


Here are the things you'll need to assemble your PCB: 

Recommended Items:


Included Components:

Please double check your components and quantities before beginning assembly. If you find that you are missing something please fill out our Component Request Form and we'll ship your missing components asap.

  • Atmega32A (1)
  • 40-pin IC socket (1)
  • USB Type-C port (1)
  • 6mm pushbutton (2)
  • 3mm Red LED (1)
  • 3mm White LED (1) Optional
  • 500mA resettable fuse 5.1mm (1)
  • 16mhz crystal (1)
  • 6 pin header (1)
  • 22pF capacitor (2)
  • 0.1uF capacitor (2)
  • Zener diode 3.6V (2) Do not mix up with 1N4148 diodes
  • 1.5K resistor (2)
  • 5.1K resistor (2)
  • 75R resistor (2)
  • 10k resistor (1)
  • 22k resistor (1) Optional
  • 4.7uF capacitor (1)
  • 1N4148 diode (~100) There will be extras


Mysterium PCB Componets




Step 1: Install 1N4148 Diodes

This part has a specific orientation! – The black bar on diode will point upward and line up with the square pad.

Bend legs straight down as close to diode as possible and insert. Solder and clip the legs. D98 marked “ISO” near left shift switch position only needed for ISO layout.





Step 2: Install (2) 3.6V Zener Diodes

This part has a specific orientation! – The black bar on diode will point upward and line up with the square pad.

These two diodes will be separated from your other diodes. They are NOT interchangeable. Use same method for soldering.





Step 3: Install Resistors

  • 1.5K resistor (2)
  • 5.1K resistor (2)
  • 10k resistor (1) if using Red LED or 22k resistor (1) if using white LED
  • 75R resistor (2)

If using the white LED make sure to use the 22k resistor instead of the 10k resistor. Reason being, the white LED is very bright when used with the 10k resistor.

These resistors do not have a specific orientation. Insert based on labeled resistor value and solder using the same method you used in steps 1 and 2.





Step 4: Install USB-C Port

Warning: This is the most challenging part of the build. Take your time and remember it's always easier to add more solder than to take it away.

Insert and flip board over. Solder only one of the large bottom legs. Heat up soldered pad and press down to ensure the port is flush before soldering the other three legs.

For the small pins you are going to use a different technique than the rest of the components. The technique is called "Drag soldering". Here's a video of how it's done.

Using your flux pen, apply flux across the pins and pads for USB-C port. Apply a very small amount of solder to the first pin and drag your iron across the pins. Repeat until all holes are filled.





Step 5: Install (2) Push Buttons 

These buttons do not have a specific orientation. Insert buttons into the appropriate holes. Turn the board over and solder one leg for each switch. Then reheat the solder joint while pushing on the button to make sure it's flush and aligned. Solder remaining legs.





Step 6: Install (1) 6-pin Header

The longer side of header is the top side. Insert the shorter side of the header into the PCB and solder only one pin. Then reheat the pin and press down from the top to align flush with the PCB before soldering the rest of the pins. Heat will transfer from the bottom of the pin to where you are pushing down. Use rag or glove to protect your hand from the heat.





Step 7: Install 500mA Fuse

This part does not have a specific orientation. Insert the fuse into the PCB, turn over and solder both pins. Flip the PCB back over and fold the fuse over to the left as pictured. 





Step 8: Install LED

This part has a specific orientation! The short leg and flat side of the LED lines up with the square pad. If you soldered in the 10k resistor in step 3 use the Red LED if you soldered in the 22k resistor use the White LED.





Step 9: Install 7uF Capacitor

This part has a specific orientation! The longer leg goes to the square pad and the white mark on the capacitor will be pointing upward.





Step 10: Install 16mhz Crystal

This part has no specific orientation. Insert the crystal into the PCB, flip over and solder only one pin. Hold down the crystal and reheat the soldered joint to align the part. Solder the other pin.





Step 11: Install (2) 22pF Capacitors

This part has no specific orientation. These capacitors are the smaller blue capacitors with straight legs.





Step 12: Install (2) 0.1uF Capacitors

This part has no specific orientation. These capacitors are the larger blue capacitors with winged/wider legs.





Step 13: Install 40-pin IC Socket and Atmega32A

Do not insert the Atmega32a microcontroller into the 40-pin socket before soldering the socket into the PCB.

Take note of the notches marked on the PCB, socket and microcontroller. It's important that they all align for proper orientation.

Solder two opposite corners of the IC socket. Reheat the soldered pins and press down on each to ensure socket is flush with PCB. Then solder the rest of the pins. Insert the microcontroller into the socket, with the notch on the left side. You may have to gently bend the pins slightly inward for proper alignment with the socket.





Step 14: Test the PCB

Plug your finished PCB into your computer. Open up VIA or similar key tester and test your keys by shorting the switch pads with tweezers. Here's a video of how to do it.





Step 15: Install Stabilizers

This case and PCB is compatible with both clip-in and screw-in style PCB-mount stabilizers. Install stabilizers into the PCB.

 photo of p.01 pcb with stabilizers installed


Step 16: Install Optional PCB Foam

With your stabilizers installed, lay included PCB foam on top of the PCB and align it accordingly. Then place the included switch plate on top of the PCB foam. If you are not using the included foam, skip this step.



Step 17: Install Switches

Install all switches into the plate making sure to align all switch pins with the correct holes in the PCB. Also, be sure to fully seat your switches in the plate. You'll hear an audible click when your switch is fully seated.

Solder all switches into place. At this point you should retest your PCB.

 close up image of keyboard switch installed into plate and PCB


Step 18: Install Case Feet

Place your assembled Plate and PCB to the side and grab the P.01 case. Flip the case over to find two horizontal channels machined into the surface. This channels are for the included silicone feet. Pull back a small amount of the adhesive backing and align the foot to the end of the channel. Slowly work your way across the channel pulling back the adhesive backing as you go and pressing down the foot. Do not pull and stretch the foot.

 close up of foot installed on the bottom of the keyboard case.


Step 19: Install Assembled Plate & PCB into Case

Place the case bottom to the site. Turn the case top upside so that you have a view of the inside of the case. Place your fully assembled plate and PCB into the top of the case making sure to align all mounting points on the plate to the appropriate mounting points on the case top. Use the included M3 fasteners to attached the assembled plate and PCB to the case top.

 image of assembled plate and pcb being screwed into the top half of the keyboard case


Step 20: Install Optional Case Foam

With the plate and PCB mounted in the case, place the included case foam on top of the PCB. If you're not using the case foam skip this step.

 image of optional case foam installed on the bottom of the PCB before attaching the bottom of the keyboard case


Step 21: Install Bottom of Case

With the case top still face down, gently lay the case bottom on top making sure to align everything appropriately. Once the bottom is fully seated, install the included m3 fasteners to seal the case.

 image of case bottom installed


Step 22: Install Acrylic Top Cover

Flip the assembled case over. Place the included Acrylic Top Cover on top and attach it with the remaining m3 fasteners. Be careful not to overtighten the screws. The Acrylic can crack.

 image of acrylic cover being screwed into place


Step 23: Install Keycaps

Pick your keycaps, Install and enjoy!

keycaps installed