In this project, we will build a circuit that is identical to a police car to create a blinking light. 555 Timer IC and ten decades counter IC have been built for this police light circuit. The timer produces pulsation and is fed into the ten-stage counter so that a flashy light is generated like a police vehicle.
This project is easy to build and requires a few components easily available in the electronic shop.
Hardware Component
The following components are required to make Flashing Police Lights Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | IC | CD4017 | 1 |
| 2. | IC | NE555 timer | 1 |
| 3. | Resistor | 1KΩ, 10KΩ, 220Ω | 1, 1, 7 |
| 4. | Electrolytic Capacitor | 10µF | 1 |
| 5. | Transistor | 2N2222 | 2 |
| 6. | LED | – | 4 |
| 7. | Battery | 6V | 1 |
CD4017 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of CD4017
NE555 IC Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of NE555 IC
Flashing Police Lights Circuit
Working Explanation
The diagram for police lighting is seen in the figure above. The timer produces flashes of roughly 100ms. The time of ON is 50ms, and the time of OFF is 50ms. You can change this time by adjusting the capacitor value.
The binary counter now counts the number of pulses indicated in a clock and causes the resulting pin output to go up, e.g., if the event count is 3, then a counter pin of Q2 is high, and if 5 counts, the pin of Q4 is high. The counters of both pulses will be calculated as the counter pin of the case. So there would be a peak for every 100ms for this peak, and so is the output.
Here, one transistor is attached to Q0, Q2, and Q4, and another transistor base is attached to Q5, Q7, and Q9. A RED LED is driven with the first transistor, and a second powers a range of blue LEDs with the second transistor.
As stated earlier, one counter output per 100ms is increased until the excess flow. The counter resets and starts from zero again when the count is overflowed.
Applications and Uses
A police light is a form of emergency lighting for cars. In ambulances, fire brigades, armed cars, etc., you can even see the same blinking lights.
