This article explains about a 9V Loud Speaker Sound Generator Circuit.
It is simple and is with low cost and it works on 9V DC power supply.
It gives loud sound compared to simple buzzer.
Therefore it is useful for alarms, door bells, alerts and projects.
Here, common transistors are used so beginners can build it easily.
Circuit Working:
Parts List:
| Components | Value | Quantity |
|---|---|---|
| Resistors (All resistors are 1/4 watt) | 1k, 4.7k, 2.7k, 68k, 1.2k, 330Ω | 1 each |
| Capacitors | Electrolytic 10uF 25V | 2 |
| Electrolytic 1uF 25V, 33uF 25V | 1 each | |
| Ceramic 0.047uF 50V | 1 | |
| Semiconductors | Transistors BC337 NPN | 2 |
| Transistor BC557 PNP | 1 | |
| Transistor 2N2222 NPN | 1 | |
| Red LED | 1 | |
| 8Ω speaker | 1 | |
| 9V Power supply | 1 |
At first the power supply of 9V is applied to the circuit and then capacitors start charging.
Because of this Q1 starts oscillation and after that the signal goes to Q2 through coupling capacitor.
Therefore oscillation becomes stronger and then amplified signal moves to Q3 stage.
At the same time LED glows showing operation and next Q3 drives Q4.
Q4 works as power amplifier and as a result speaker gets high current.
So loud buzzer sound is produced and thus whole circuit works as sound oscillator and amplifier.
How to Build:
To build a 9V Loud Speaker Sound Generator Circuit follow the connection steps:
- Assemble all the parts as shown in circuit diagram.
- Capacitor C1 positive connect to Vcc and negative to GND.
- Q1 2N2222 emitter connect to ground
- Base connect to R2 and cathode of C4 junction
- Collector connect to R1 and anode of capacitor C2.
- Q2 BC337 emitter connect to ground.
- Base connect to cathode of capacitor C2 and resistor R3.
- Collector connect to anode of C3 capacitor and capacitor C4 and Vcc.
- Q3 BC337 emitter connect to anode of LED and cathode connect to collector of Q2.
- Base connect to resistor R5 one end and R6 resistor.
- Collector connect to base of transistor Q4 through resistor R4.
- Q4 BC557 emitter connect to Vcc.
- Base connect to R4.
- Collector connect to C5 capacitor one end and one end of speaker.
- Speaker other side connects to ground.
Conclusion:
This 9V Loud Speaker Sound Generator Circuit is simple
It uses easily available parts which produces strong sound output.
Therefore it is suitable for alarms and alerts.
Moreover beginners can understand transistor working.
Finally this circuit is reliable and easy to build.