Assembly

This section explains how to assemble a SquishBox from a kit, or from individually sourced parts after obtaining a fabricated PCB, printing an enclosure, and gathering the required through-hole components.

Components

In addition to the PCB (with surface-mount components pre-installed) and the 3D-printed PLA enclosure, a standard SquishBox kit includes:

  1. 16x2 character LCD

  2. 1x6 male header strips (2)

  3. 2x20 female header

  4. 10K trimmer potentiometer

  5. 1/4” TRS audio jacks (2)

  6. 2x2 male headers (2)

  7. Jumper blocks (2)

  8. Rotary pushbutton encoder + knob

Optional / Deluxe model:

  1. Momentary footswitches (2)

  2. 5mm LEDs (2)

Photo of SquishBox kit components

Through-hole components for the SquishBox

Electronics

General soldering tips:

  • Install components on the side of the PCB with the matching silkscreen outline.

  • Seat components flush against the PCB, especially the rotary encoder, audio jacks, and 2x20 header, so everything aligns properly with the enclosure.

  • Install the LCD last, as it covers several other solder points.

PCB Orientation

The surface-mount components are on the PCB “bottom” side, which faces the Raspberry Pi when installed.

Install these parts on the bottom side:

  • Audio jacks

  • 2x2 headers

  • 2x20 female header

  • Trimmer potentiometer

Install these parts on the top side:

  • Rotary encoder

  • LCD module (last)

audio jacks flush mounted to bottom side of PCB

Proper component mounting

MIDI Jumper Configuration

Headers J2 and J3 configure the MIDI TRS jacks for Type A or Type B wiring using jumper blocks.

As marked on the silkscreen:

  • Type A: Horizontal connection ( = )

  • Type B: Vertical connection ( ‖ )

jumpers installed in horizontal position

MIDI minijack jumpers in type A configuration

LCD Header

The center four LCD pads (D0-D3) are unused.

Solder the 1x6 male header strips to the outer pads at each end of the LCD connector.

LCD with male headers soldered to outer 6 pads on each end

Correct installation of pins to LCD connector

Deluxe Components

The Deluxe model adds two LEDs and two momentary footswitches.

LED Installation:

Insert the short leg (cathode / ground) of each LED into the square notched pads on header P1, positions 4 and 7. These pads connect to ground through 1K current-limiting resistors. Insert the long leg (anode / positive) into neighboring pads 3 and 8.

Leave enough lead length above the PCB so the LEDs can reach the enclosure openings before soldering.

LEDs sticking out of PCB

Proper LED mounting

Footswitch Wiring:

Strip and tin four short wires (about 3 cm each).

Wire the switches as follows:

  • Connect one lug of each switch to P1 pads 12 and 13 (GPIO9 and GPIO10)

  • Connect P1 pad 14 (GND) to the remaining lug of one switch

  • Bridge that grounded lug to the remaining lug of the second switch

footswitches wired to PCB

Footswitch wiring

Enclosure

Align the rotary encoder shaft, LEDs (if installed), and audio jacks with the corresponding enclosure openings.

Press the PCB into place and secure it using the washers and nuts supplied with the rotary encoder and audio jacks. Mount stompswitches if used.

PCB mounted in 3D printed enclosure

PCB mounted in enclosure

Install the Raspberry Pi by plugging its GPIO header into the 2x20 socket.

Secure the lid using the three included screws.

Raspberry Pi plugged into PCB

Raspberry Pi Installation