Product applations:
It can be used to monitor a variety of weather conditions, and turned into a number of fixed signal and AO output.

To make this project, you will need some supplies:
1. Kuman Arduino UNO board*1
2. Kuman DHT11 sensor*1
3. Kuman Soil Moisture Sensor Kit*1
4. Dupont cables
Sensor features:
1. The sensor uses a high quality FR-04 double-sided materials, large area 5.0*4.0CM, and with nickel plated surface, with a more superior performance against oxidation, electrical conductivity, and life expectancy
2. The comparator output and signal are clean, with good waveform, and strong driving ability, more than 15mA
3. With potentiometer adjustment sensitivity
4. Working voltage 3.3V-5V
5. Output mode: digital switching output (0 and 1) and analog AO voltage output;
6. A fixed bolt hole, easy to install
7. Small size: 3.2cm x 1.4cm PCB
8. Using a wide voltage LM393 comparator
Function introduction:
Steps:
1. Connected to the 5V power supply, power indicator light, no water droplets on the sensor board, the DO output is high, the switch lights off, a drop of water, DO output is low, the switch indicator light
2. Brush off the water droplets above, and restored to the output high level state.
3. AO analog output, can be connected to the AD port of the microcontroller to detect the drop in the above amount of rainfall.
4. TTL DO digital output can also be connected to the microcontroller to detect whether there is rain.
Connections:
VCC: connected to the power supply cathode (3-5V)
GND: connected to the negative electrode
DO:TTL switch signal output
AO: analog signal output
Code:
#define Moisture A0 //The definition of AO pin IO-A0
#define DO 7 //The definition of DO pin IO-7
void setup() {
pinMode(Moisture, INPUT);//Define A0 as input mode
pinMode(DO, INPUT);
Serial.begin(9600);
}
void loop() {
//Returns the serial measurement data
Serial.print("Moisture=");
Serial.print(analogRead(Moisture));//Numerical read AO
Serial.print("|DO=");
Serial.println(digitalRead(DO));//Numerical read DO
delay(1000);
}