Simple White Noise Generator Circuit is DIY project.
It make sound like radio hiss or static.
Circuit is used for sound effect, privacy noise and testing audio tools.
Noise come from electronic parts.
We can use resistor or reverse transistor for noise.
Capacitor remove too high or too low sound.
Circuit Working:
Parts List:
| Component Type | Description | Quantity |
|---|---|---|
| Resistors | 6.8k 1/4 watt | 1 |
| 68k 1/4 watt | 1 | |
| Capacitors | 4.7μF 50V | 1 |
| Semiconductors | Transistor BC547 | 1 |
| Zener diode 10V | 1 |
This circuit make white noise using BC547 transistor.
Noise come from 10V Zener diode in reverse and is connected to transistor base.
Zener is main part for making noise.
Diode must be in correct direction.
Two resistors control current.
4.7uF capacitor remove bad high or low sound and shape noise.
Need high voltage to about 24V for strong noise.
Can build on PCB then just copy diagram and connect parts to right pads.
Formulas:
We can make simple white noise circuit using transistor noise.
Here is easy formula for noise voltage:
en = √(4kB * T * R * f)
where:
- kB is Boltzmann constant with 1.38 × 10⁻²³ J/K
- T is temperature in Kelvin
- R is resistance
- f is bandwidth in hertz
White noise have flat sound over big frequency range.
We must test different parts and values to get good white noise.
Easy circuit use resistors, Zener diode and BC547 transistor which has it has own noise.
Try different resistor values to get best noise for our use.
How To Build:
To build a Simple White Noise Generator Circuit follow the below mentioned steps:
- Gather all parts like BC547 transistor, 10V Zener diode, resistors R1 and R2 and capacitor C1.
- Connect collector of Q1 to +24V through resistor R1.
- Connect base of Q1 to 10V Zener diode.
- Connect emitter of Q1 to ground.
- Connect resistor R2 between collector and Zener diode.
- Connect capacitor C1 from Zener diode to ground.
- Take noise output from point between R1 and collector of Q1.
Safety:
- This circuit uses high voltage 24V to 26V not like small 9V ones.
- If anyone is new to electronics then ask help before working with high voltage.
Conclusion:
Simple White Noise Generator Circuits use Zener diode and BC547 transistor.
It make static sound by boosting and shaping noise from parts.
Needs high voltage from 24V to 26V to work well.
Build on PCB for clean design and be careful with high voltage.
References:
Understanding the circuit diagrams for white noise generators