How To Get The PCB?

This is a tricky question. If you never made a PCB and you don't want to try it, maybe I can help. I can make a few in a month but it's depending on my free time, and suppliers( shortage... ). If you are in trouble with the PCB you can contact me and I will try to help.

The other option is to create the PCB for yourself. It is not that hard actually, you need a good soldering iron and a tweezer. There are a ton of videos online about soldering, but here is my preferred one:

You also need some naked PCB panels, I highly recommend JLCPCB. It is cheap and fast. The quality for this price is very good, and the interface is simple. Just upload the gerber files and fill inthe settings as shown below:

JLCPCB Settings

Note: Please check the settings twice. A wrong setting can be a huge price difference!

How To Get PCB Components?

The whole PCB is designed with KiCad and it has a very useful plugin called Interactive HTML BOM. This plugin generates a browser-based interactive tool, where you can find all the components needed for the board. Also, it shows where those components shall be placed on the PCB.

Note: On smaller monitors, you may open this document separately.

Of course, if you don't like the browser version of the BOM, you can open the whole project with KiCad.

Schematics

This section explains the different modules and their job on the panel. You can skip this part if you are not interested in circuit design.

Note: On smaller monitors, you may open this document separately.

Analog Stage

This part consists of seven amplifier stages:

Microphone Preamplifier: The condenser microphone generates a very low amplitude signal. This stage amplifies this signal to make it usable for the other stages. Also, this amplified signal is connected to the A3 ADC channel by default.
Half-Wave Rectifier: This stage consumes two amplifiers. In this configuration, it is a peak detector. The software is using this signal to detect the noise floor of the environment. It is connected to the A2 ADC channel.
Low-Pass Filter: This stage attenuates frequency components above 500Hz. It could be used for something, but this signal is not used by default. If you want, you can switch the state of JP1 and JP2 jumpers to use this channel. In this way, it will be connected to the A3 ADC channel instead of the preamplifier output. The software does not support it, you have to implement it if needed.
High-Pass Filter: This stage attenuates frequency components below 2000Hz. It is connected to the A1 ADC channel.
Band-Pass Filter: The last stage consumes two amplifiers. It has a pass band between 500Hz and 2000Hz. That means it passes all frequency components in this range, but outside this band, it attenuates.

Half-Supply Generator

This part generates exactly half of the supply voltage. The filters need a reference voltage between the power rails to swing the output voltage up and down. This is why we need a half-supply generator. Also, this means that the filter's output voltage is shifted to half supply instead of 0V.

Power Input

This section is responsible to supply the circuits safely. It has a thermal fuse, a TVS diode, and polarity protection. I tried to make this as safe as possible.

Endstops

The endstops are just simple switches, they have to be debounced. This simple part does this job.

Buzzer Driver

The panel has a small buzzer. It is useful to create some interaction when you navigate the menu. This section consists of a transistor, that drives the buzzer, and some power filtering. The driver stage has a protection diode, so both electromechanical and piezoelectric buzzers can be used.

Display Interface

This is just a connector for the display cable with two pull-up resistors for the I2C signals. It also has some power filtering.

DC-Motor Driver

The circuit is the same as the buzzer driver. Its job is to drive the motor.

Humidifier Switch

The circuit is the same as the buzzer driver. Its job is to turn on or off the humidifier module.

LED Interface

This contains two connectors for the two LED strips and some power filtering. It also has some series resistance, which is required to use the WS2812 and WS2813 chips properly.

Encoder Interface

The encoder is three switches, they have to be debounced. This section does this.

PCB Test

After you have assembled the PCB it is necessary to test it, before connecting it to the Arduino. This is the smoke test. The best method is to have a bench power supply, and power up the board with s 5V and 100mA current limit. The power LED should turn on, and the current consumption should be less than 50mA( for just the bare PCB ).
If the smoke test succeeds it's time to connect the PCB to the Arduino UNO and upload the firmware to it. If you can program the Arduino without a problem that is a good sign.
Lastly, you have to connect all the peripherals to the board and try them before the final assembly. For this step, you need all the peripherals and cables to be prepared. Every connector is labeled on the PCB, so you can find the right one for each peripheral easily.
If everything works, you can jump to the final assembly.

Note: If the smoke test fails, and the current consumption is high, you probably assembled one or more components wrong. To identify the problem, there are some practices. For example, if something blows up, it has to be replaced without a question. Also if a component gets hot for the touch it is probably dead, I recommend replacement. Also, check the IC-s and silicon-based component's orientation. If they are soldered in the wrong orientation they usually die at power up.

Cable Preparation

Power Connector Cable

The cable length from the connector to the end sleeves is approximately 110mm, the cable is 0.22mm2 ( 24 AWG ), and the ends have cable end sleeves. The connector, that I used can be found here.

Warning: Always check the polarity with a multimeter, before connecting to the PCB! The best practice is to mark the cable with a label printer or some kind of sticker.

Humidifier Cable

The cable length from the humidifier to the end connector is approximately 140mm, the cable is 0.22mm2 ( 24 AWG ), and the end has a PHR-2 JST connector. The connector, that I used can be found here. The crimping tool for the connector, that I used can be found here.

Humidifier Back

The polarity is marked at the back side of the humidifier board. Also, a little solder bridge has to be made to turn on the humidifier without a button press. The humidifier module, that I used can be found here.

Warning: Always check the polarity with a multimeter, before connecting to the PCB! The best practice is to mark the cable with a label printer or some kind of sticker.

LED Disc Cable

LED Disc Connector

The cable length from the LED disc to the end connector is approximately 160mm, the cable is 0.22mm2 ( 24 AWG ), and the end has a PHR-3 JST connector. The connector, that I used can be found here. The crimping tool for the connector, that I used can be found here.

Note: The cable has to be soldered to the bottom of the LED disc. The bottom side has SMD solder terminals where the cable has to be soldered. They are labeled, so it's easy to identify the wires. There is an input and an output connector, the input one has to be used.

The LED disc, that I used can be found here.

LED Strip Cable

LED Strip Connector

The cable length from the LED strip to the end connector is approximately 130mm, the cable is 0.22mm2 ( 24 AWG ), and the end has a PHR-3 JST connector. The connector, that I used can be found here. The Crimping tool for the connector, that I used can be found here.

Note: The LED strip has to be cut to length with 27 LEDs. The wires have to be soldered. If the strip is made with WS2813 LEDs, the BI ( Backup Input ) pin has to be soldered to the ground. Also, a 470uF 10V capacitor has to be soldered to the input across VCC and GND on the strip to stabilize the power rail. The width of the capacitor has to be equal to or less than the LED strip( which is 10mm ).

Warning: The polarity of the capacitor has to be correct, otherwise, it will blow up.

LED strip, that I used can be found here.

Oled Display Cable

Oled Display Connector

The cable length from the Oled display to the end connector is approximately 210mm, the cable is 0.22mm2 ( 24 AWG ), and the end has a PHR-4 JST connector. The connector, that I used can be found here. The display side of the cable also has a connector, it can be found here. The crimping tool for the connector, that I used can be found here.

The oled display module, that I used can be found here.

Encoder Cable

Encoder Connector

The cable length from the encoder to the end connector is approximately 200mm, the cable is 0.22mm2 ( 24 AWG ), and the end has a PHR-5 JST connector. The connector, that I used can be found here. The crimping tool for the connector, that I used can be found here.

The encoder module, that I used can be found here.

Note: On the encoder side, the wires have to be soldered to the pins on the encoder module. Use heat-shrink tubes to isolate the wires from each other.

Front Endstop Cable

The cable length from the front endstop to the end connector is approximately 155mm, the cable is 0.22mm2 ( 24 AWG ), and the end has a PHR-2 JST connector. The connector, that I used can be found here. The crimping tool for the connector, that I used can be found here.

Note: Because it is a mechanical switch, the polarity off the connector doesn't matter.

The endstop switch, that I used can be found here.

Back Endstop Cable

The cable length from the back endstop to the end connector is approximately 155mm, the cable is 0.22mm2 ( 24 AWG ), and the end has a PHR-2 JST connector. The connector, that I used can be found here. The crimping tool for the connector, that I used can be found here.

Note: Because it is a mechanical switch, the polarity off the connector doesn't matter. The endstop switch, that I used can be found here.

Back Motor Cable

Motor Cable

The cable length from the motor to the end connector is approximately 105mm, the cable is 0.22mm2 ( 24 AWG ), and the end has a PHR-2 JST connector. The connector, that I used can be found here. The crimping tool for the connector, that I used can be found here.

Note: Because of the mechanical construction of the open mechanism, the polarity on the connector doesn't matter.

DC motor, that I used can be found here.