Various type of switching circuit like a touch-operated relay, light operated relay, heat operated relay is already posted in bestengineeringprojects.com. Now here is another simple electronic project in the series of switching circuits called sound-operated relays. Circuit Description of Sound Operated Relay using Transistors The circuit of sound operated relay is self-explanatory and is very easy to understand. This circuit is built around a 2-stage audio amplifier using PNP transistors. The sound sensor of the circuit sound-operated relay is done by 8Ω loudspeakers. The output of the loudspeaker is given…
Modems have been often been stand-alone, add-on devices for most data communications equipment. The recent integration of the complex functions a modem performs into a single chip has allowed manufacturers to economically build the modem right into the microcomputer or data terminal equipment. A circuit diagram of such a modem is shown in figure 1. Circuit Description of Medium Speed Modem Using SC11004 All of the signal processing functions needed for a full-duplex, 300/1200-b/s modem, including the FSK and PSK modulators and de-modulators, are integrated on a single chip. It includes…
Here, we have listed 50+ Top 555 Timer IC Projects. The 555 timer projects posted here are useful for every electronics hobbyist. As we know, timer IC has much more application thus it is the most widely used general-purpose timer IC. It is used in various categories of projects like PWM amplifier, delay time, switching circuit and it can be also used in clock pulse generators, duty cycles, etc. A host of application notes, magazine articles, and even kits are on the market for many different applications of the IC…
The compression and expansion are two important techniques used by audio engineers during recording and reproduction of program material. The compression of dynamic range of program material (records, speech or musical broadcasting) permits maintaining constantly high modulating level while the expansion, when used with the reproduction of compressed material, restores the dynamic range and creates a ‘live’ music. Thus, we are created simple and basic project Expander Compressor Unit Circuit. Circuit Description of Expander Compressor Unit Circuit | Compander Creating these effects is costly and complex, and beyond the scope of amateur…
The project “Steam Whistle Circuit using 741 IC” produces a sound similar to that of a steam locomotive whistle. Here, in the circuit Transistor T1 and T2 from a multivibrator, the frequency of which is set by preset VR3. This is the ‘toot’ part of the whistle. Transistor T4 amplifies white noise generated across the reverse-biased transistor T3. White noise and toot mixed by IC1. The ratio of these is set by preset VR2. IC1 is the most popular and low-cost IC 741 and is used as a low-frequency multivibrator,…
Discover how a woofer and tweeter matcher circuit enhances audio systems by producing balanced sound. Learn how specialized components optimize low and high frequencies, leading to an enjoyable listening experience. Introduction: A speaker’s frequency response plays a crucial role in delivering high-quality sound across the audible spectrum. However, not all speakers can reproduce frequencies uniformly, leading to an imbalanced sound output. To overcome this challenge, audio systems incorporate specialized components known as woofers and tweeters, each optimized for handling specific frequency ranges. Woofer and Tweeter Function: Woofer: A woofer is…
A signal which contains almost all frequencies is called white noise. In an audio system white noise contains only audible frequency. The white noise of the electrical system is analogous to white light from optics, where white light contains all frequencies or colors. White noise is mostly used in the testing audio equipment like pre-amplifier, power amplifiers, filters, etc. Check out the article on Electrical noise | Types of Electrical Noise. So, today in this article we are going to describe a simple white noise generator circuit. This circuit can…
An automatic lead acid battery charger circuit is designed to charge 12V, and 40Ah in different charging modes i.e. boost mode and float mode. This circuit can be used to charge large-capacity inverter batteries by replacing transformers and power transistors with higher ratings. To know the condition of the battery and charger unit, this circuit was incorporated with an audiovisual indication unit. Before going to the circuit description and working let’s see its salient features: Features of Automatic Lead Acid Battery Charger Circuit Automatic charger the battery and maintain the…
This article is dedicated to those who want to make their high-quality low distortion 10 band graphic equalizer circuit. Before going to the circuit and it’s working let’s understand an equalizer and its types. An equalizer is simply a device that is attached to an instrument and with the help of this equalizer, we can set bass, middle, or treble. Sound or audio has a spectrum where frequencies are classified into different ranges. So, what are these bass, middle and treble? These are the range of frequencies, where the bass…
Power supply has been considered a role in an electronic circuit. Power supply furnishes the voltage and current requirements for electronics circuit operation but the problem is most of the electric power is generated as AC power. But for the operation of most of the electronics circuits, we need a DC power supply. Sometimes the output of the power supply consisting unwanted ripple components i.e. component of supply frequency and its harmonics. We should take care of this unwanted noise or harmonic components because this might cause problems (especially in…
