Archive for category: Audio and Amplifier

Audio Frequency Generator Circuit

Audio and Amplifier | By: Diagram mania

This audio frequency generator is a triggered signal generator. When a positive pulse of about 6 volts (minimum) is fed to the circuits input , a modulated audio signal comes out of the output. The signal pattern is similar to a bird’s chirp. The pulse width of the trigger signal must be a minimum of […]

Audio Equipment Autodisconnecting Circuit

Audio and Amplifier | By: Diagram mania

This simple circuit disconnects equipment rack of your audio in case has not delivered a sound a specified period. Circuit is operated by pressing his S1, which produces loading of C1. Further, switch IC1b AO exit in the state “up” and the audio equipment is powered from the network through semiconductor relay ISO1. LINE OUT […]

Automatic Gain Control Circuit

Audio and Amplifier | By: Diagram mania

The automatic gain control circuit AGC provides a signal with less harmonics and additional amplification, between certain limits. As a result, it eliminates those intensity differences, annoying, and of speech music, which sometimes appear on radio and television. Field effect transistors T1 is used as a variable resistance. It’s value can vary from infinity to […]

DIY Tremolo Effect Circuit

Audio and Amplifier | By: Diagram mania

This tremolo effect circuit uses the XR2206 and the TCA730 IC which is designed as an electronic balance and volume regulator with frequency correction. The circuit is usefull for stereo channels and it also has the ability to simulate the Lesley effect aka rotating loudspeaker effect. How does the tremolo effect circuit works Balance and […]

Classroom Microphone System Circuit

Audio and Amplifier | By: Diagram mania

This audio amplifier circuit is useful in classrooms to reduce the strain of lecturing ,if the surrounding environment is noisy. It uses the power amplifier IC LM380 that gives 2 watts output which is sufficient in a confined area. The amplifier is portable and the whole circuit and the battery can be enclosed in the […]

Class A Preamplifier Circuit

Audio and Amplifier | By: Diagram mania

This class A preamplifier has been designed in a symmetrical structure. In the input differential stages we’ve used the dual transistors T1 and T2. Polarisation correction is essential because of the amplification differences and is assured with T12. P2 brings the output voltage to 0. For maximum performances, T7 and T9 surfaces must be in […]

Car Audio Amplifier TDA1557Q TDA1553Q

Audio and Amplifier | By: Diagram mania

This stereo audio amplifier is for car purpose and can deliver up to 2 x 22W using a single TDA1557Q or TDA1553Q IC from Philips. TDA1557Q TDA1553Q datasheet

AVC Automatic Volume Control Circuit

Audio and Amplifier | By: Diagram mania

AVC – The featured circuit controls a volume line automatically. It delivers an output voltage of approximately 4 volts peak to peak. This voltage remains relatively constant by input voltages ranging from several hundred milivolts to serveral volts. This electronic circuit is not highly recommended for Hi-Fi applications because its noise factor is way above […]

UM3561 Siren Generator Design

Audio and Amplifier | By: Diagram mania

UM3561 is an excellent ROM IC that can generate Multi siren tones simulating Police siren, Ambulance siren, Fire brigade siren and Machine gun sound. This 8 pin low power IC can work down to 2.4 volts. The UM 3561 is a low cost siren generator designed for use in toy applications. The IC has an […]

Electronic Cricket Sound Generator

Audio and Amplifier | By: Diagram mania

Why an electronic cricket Many people like the cricket sound specially if they live in a big town. This electronic cricket circuit works in pulses, so the battery life is prolonged, the current consumption is just 2mA. The electronic cricket schematic is very simple, it is build with CD4049 or CD4009 wich is CMOS Hex […]