CSE252 Electronics final project (Yanbu Industrial College). A simple circuit that detects three water levels using transistors and LEDs, with no microcontroller.
Team: Wejdan Aljohani, Rama Ayman
The detector measures the water level and shows it with three LEDs. Each LED is driven by a BJT (bipolar junction transistor), so as the water level rises, more LEDs turn on.
- Input: different water levels from a water source
- Output: LED colors showing the level
- Goal: a working water level detector built around transistors
- BJT transistors (one per LED)
- LEDs: red, blue, green
- Resistors
- Jumper wires
- Battery
- Breadboard
- Multimeter (used to check resistor values)
| Water level | LEDs on | Photo |
|---|---|---|
| Low | Green | ![]() |
| Mid | Green + Blue | ![]() |
| High | Green + Blue + Red | ![]() |
- Electrical circuits
- Breadboard prototyping
- Hardware testing
- Circuit design and troubleshooting
- Using a multimeter to check resistor values
- Teamwork
- Technical presentation
- Documentation










