Nyquist/Levinson Rev. 3 Keyboard PCBs - 60%/40% Split Ortholinear

The Nyquist is a 60% split ortholinear keyboard, that can also be converted easily to a 40% split ortholinear by breaking off the bottom row (by hand).

Nyquist/Levinson Rev. 3 info:

The Nyquist Rev. 3 features an on-board controller (ATmega32u4) with DFU bootloader and USB-C port. The PCBs are compatible with the currently available Nyquist cases and the SP50 case. The bottom row can be broken off to turn it into a Levinson (no 2u support in that configuration). Supports MX, Alps, and Kailh Choc switches. 6 RGB underglow LEDs on each half.

Nyquist Rev 3 kit contents:

• Just a left PCB and right PCB, that's all that's needed

Nyquist Rev. 2 kit contents:

• 2 PCBs
• 2 TRRS Jacks
• Diodes (enough for build)
• 2 4.7kΩ resistors for I2C

Layout

Each half of the board is a 5x6 matrix, but there is the option to have a 2u key in the lower left and right corners in place of 2 1u keys. The spot for the 2u has holes for Cherry PCB mounted stabilizers.

The Name

The name Nyquist comes from the Nyquist sampling theorem, which says that if you want to sample a signal to convert it from analog to digital and be able to uniquely reconstruct the signal later, then the sample rate has to be twice the bandwidth of the signal. So here, if you want to sample this PCB, you're going to need 2 of them.

Firmware

The Nyquist uses QMK for its firmware, and the code for it has been merged into the main codebase. You can find it here: QMK - Nyquist directory. If using the Rev. 3 board in 4x12 mode, also use the Nyquist firmware, just use LAYOUT_ortho_4x12 in your keymap.

Case

Here's the case files for a sandwich-style case are available here: Nyquist Case Files

The kerf setting was set to 0.15mm for use with Lasergist and Ponoko.

Items needed for build

• Switches - Alps or MX-compatible
• Case - We have a few different types available
• Acrylic
• Stainless Steel
• PCB plates
• TRRS cable
• Micro USB cable (if using Pro Micro on Rev. 2) or USB-C cable (Rev. 3 or Elite-C on Rev. 2)
• Optional - 2u PCB mount MX stabilizer if using 2u keys
• The following parts are for Nyquist Rev. 2 only:
• 2 Pro Micros or 2 Elite-Cs (can do 1 Pro Micro and 1 Elite-C)
• Optional - LED add-on kit for in-switch LED support (not underglow)
• Optional - 470Ω resistors for in-switch LEDs

Build Guide: Build for Rev. 3 is similar to the Iris Rev. 3/4, a better guide is in the works. Rev. 2 build is similar to Iris Rev. 2.