Pink noise generator
In this circuit, the first 2N2712 transistor is configured in a reverse-biased manner, which creates a noise source due to the random movement of charge carriers across the pn junction. This noise generation is fundamental in applications requiring random signal generation, such as in testing audio equipment or synthesizing sound.
The second 2N2712 serves as an audio amplifier, amplifying the noise generated by the first transistor to a level suitable for listening. The gain of this amplifier can be adjusted by varying the biasing resistors connected to its base, allowing for flexibility in output levels.
The inclusion of a 0.005 µF capacitor across the output of the amplifier is critical in shaping the frequency response of the circuit. By filtering out high-frequency noise, the capacitor helps to produce a signal that approximates pink noise, characterized by equal energy per octave, which is often used in sound testing and acoustic measurements.
The output of the amplifier can be interfaced with high-impedance earphones, making the circuit suitable for personal listening applications. Alternatively, it can be connected to a driver amplifier, which can drive larger speakers, making this circuit versatile for different audio output scenarios. The design allows for easy integration into various audio systems, providing a compact and effective solution for noise generation and amplification.A reverse-biased pn junction of a 2N2712 transistor is used as a noise generator. The second 2N2712 is an audio amplifier. The 005 µf capacitor across the amplifier output removes some high-frequency components to simulate pink noise more closely The audio output may be connected to high-impedance earphones or to a driver amplifier for speaker listening. 🔗 External reference
Related Circuits
This relaxation oscillator circuit utilizes diodes to create charge and discharge paths for capacitor CI. The duty cycle is determined by resistor R2, while the frequency is controlled by resistor R4. The value of capacitor CI can be adjusted...
This resonance generator circuit, also known as an oscillating sound generator, is designed using the CMOS integrated circuit 4011 (Quad 2-Input NAND Gate). It consists of four NAND gates. Each oscillator circuit utilizes two gates. The circuit is capable...
A mechanical power source is required, such as a turbine powered by falling water, a wind turbine, a gas turbine, or a steam turbine. A shaft from one of these devices is connected to a generator to produce power....
This circuit generates sine wave oscillations, but it can also be modified to produce triangle or square wave functions. The frequency is adjustable by varying the current. By disconnecting the 20k resistor (RIN) from the reference (REF) pin (pin...
This circuit generates a two-tone effect similar to the cuckoo song. It can be utilized for doorbells or other applications due to its integrated audio amplifier and loudspeaker. When used as a sound effect generator, it can be connected...
For use with low-power transmitters that require a positive keying voltage. The transistors Q1, Q2, and Q3 are configured as a switching amplifier. When the key is pressed, the collector of Q3 is pulled to ground, which activates Q5...