Rain Alarm 555 Timer Project

This project, was an introduction to building an electronics system. The goal was to make a rain alarm in which a rain detection sensor would sound an alarm if the sensor detected moisture.

There are many real life examples where this circuit could be useful. Some examples include:

1. Outside near a garden to know if the garden is being watered or not by moisture.
2. In a basement where water may leak. There are probably other sensors that could be more efficient but this one would certainly work.
3. Outside in general to know whether it is raining or not.

While constructing this project, I originally intended to install a few rain sensors in parallel, which I eventually decided not to due to simplicity and it being my circuit board build.

The components used included:

1. A Bread Board to assemble all of the components.
2. A 12 Volt Rain detection sensor, with a relay control module potentiometer.
3. A 555 Timer
4. Three transistors: Two BC547 and One BC557
5. Jumper wires
6. Any audio speaker
7. 6 Resistors including: (1k, 10k, 33k, 39R, 47k, 100k,)
8. 2 Capacitors each (10n)

Unfortunately, as my first time I didn't think much of taking pictures of each step in the processes. In addition, I was too excited that it worked in the end that I did not capture a video of the speaker making noise as the sensor went off. This build took more time than I expected because the circuit would not properly work for a large amount of time. After much time problem shooting everything, it turns out that the issue was a transistor that was working improperly.

Step 1: Gather all the materials

Step 2: To verify the resistance of each resistor, use a multimeter to double check.

Step 3: Follow the diagram and connect each component accordingly. Some advice it to make sure the transistors are correctly aligned with base and emitter. The circuit board that I used had voltage and ground built into it.

Step 4: Add moisture to the sensor and hear the wonderful noise of the circuit working correctly.