1. Prepare Parts

In this section, we will explain how to prepare parts for PCB assembly. If you need any help with tools or wiring, please refer to Custom Wiring section.

Have in mind that dimensions recommended here are suitable for our version of 3D-printed housing. If you are using different type of housing, adjust dimensions according to it.

1.1. LED Ring

For our first component, we will go with the new LED Ring.
First, you will need to solder three wires to the bottom of the ring. The recommended length of all three wires is 35 mm.

Solder red wire on the pin that reads VCC (5V power), black wire on the GND pin (ground) and yellow wire on IN pin (data in).*

You can use any wire color you have available instead of yellow.

Soldered LED Ring is displayed in the picture below.

1.2. BME280 Sensor

Second component is BME280 temperature, humidity and pressure sensor.

Here, you just have to solder pin headers (4 pins with 2.54 mm pitch) that came with breakout module in the packaging.

Make sure that BME280 sensor (little silver cube on the breakout module) is facing upwards.

Soldered BME280 sensor is displayed in the picture below.

1.3. NodeMCU Pin headers

The next step is to prepare female pin headers for NodeMCU.

These pin headers with the pitch of 2.54 mm come in an array of 40. Our NodeMCU has 15 pins on one side, so we will need two arrays of 15 pins.

Simply cut two arrays of 15 pins from one array of 40 pins.

Cut pin headers are shown in the picture below.

1.4. PM Sensor Wires

The last step in parts preparation is to cut wires for the PM sensor and its PCB connector.

Since PM connectors are produced with connectors on both sides, you will have to cut it from one side. Before cutting, feel free to completely remove (cut) these wires:

Red
Black
Yellow
White

The length of the remaining (Green, blue, orange and purple) wires should be 35 mm.

Also, the insulation should be removed on the length of about 5 mm.

The final look of the PM sensor wires is shown below.