Moisture/Humidity measurement device

There is one spare Pico ADC, so why not add a further sensor such as a SFH 300 phototransistor for measuring the ambient light.

A rather lackluster attempt to create a protecting layer with cast resin for the PCB bottom side.

Implemented IoT capabilities (via ESP8266), i.e. value(s) can be fetched thru a web-browser. 

Wiring ESP8266 - Pico:

Pin 1: GND
Pin 2 (TXO): Pico GP5 (UART1 RX)
Pin 4: 3.3V
Pin 7 (RXI): Pico GP4 (UART1 TX)
Pin 8: 3.3V
Other pins n.c.