Loud Horn Circuit serves in almost all vehicles to give out warning signals to an incoming vehicle. Loud Horn Circuit is a good quality low-cost DIY electric horn project. We are using 555 timer IC in this project which generates an electric horn that is later amplified through a transistor.
The 555 timer IC is one of the most popular and widely used IC. It is a highly stable device for oscillation applications and generating accurate time delays. This IC has three operating modes i.e., bistable, monostable, and astable mode. The gain and tone of this electric horn can easily be varied. This circuit doesn’t need many components which makes it super easy to fit in a small box.
Hardware Components
The following components are required to make Loud Horn Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | IC | NE555 Timer | 1 |
| 2. | Speaker | 8 ohm | 1 |
| 3. | Resistor | 22K, 47K, 120Ω, 4.7Ω | 1, 1, 1, 1 |
| 4. | Potentiometer | 100K | 1 |
| 5. | Ceramic Capacitor | 18nF | 1 |
| 6. | DC Supply | 9-12V | 1 |
| 7. | Electrolytic Capacitor | 100µF | 1 |
| 8. | Breadboard | – | 1 |
| 9. | Darlington Transistor | TIP125 | 1 |
NE555 IC Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 555 Timer
TIP125 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of TIP125
Loud Horn Circuit
Working Explanation
This circuit is simple, it has IC, transistor, and speaker as main components along with a few passive components working of this circuit is as follows.
- The operating voltage of this circuit is 9-12 volts, the horn will be the loudest on 12V.
- The 555 timer IC is the heart of this circuit which is wired as an astable vibrator.
- To limit the current, we use different resistors, a variable resistor of 100K sets the desired tone of the horn by varying the resistance.
- TIP125 Darlington transistor is amplifying the output of the 555 timer IC, the amplified output (horn) then plays through the speaker.
- The speaker should be 8 ohms and 1-5 watts loudspeaker. For Noise cancellation, capacitors are used.
Applications and Uses
This circuit can be used for various purposes
- Horn for bikes, cars, scooters, cycles, etc.
- Siren circuit
- Buzzer circuit
- Alarm circuit
- Warning sirens indicating danger relating to hazardous substances such as Chemicals.
