Description. Here is a simple rain alarm circuit that produces an audible alarm when ever rain falls. The rain detector circuit is based on two transistors (Q1 & Q2) and a NE555IC (IC1). The two transistors are wired as a switch which goes on when the base of Q1 is shorted to the positive of […]
Transformerless power supply Circuit Description Here is a low cost and simple circuit that can be used to power up small electronics devices. The power is directly tapped from the mains via resistor R1. D1 rectifies the voltage and C1 and C2 are used to filter the output. The zener diode D2 will regulate the
USB LED Lamp Circuit Description Here is a simple USB powered lamp that can be used to light your desktop during power failures. The circuit operates from the 5 Volt available from the USB port. The 5V from the USB port is passed through current limiting resistor R2 and transistor Q1. The base of transistor
In this project, let’s build a simple Remote controlled switch for appliance controlling. If you know basic concepts of electronics, this circuit is pretty easy to build and test. The core of this circuit are two IC’s – which are infra red sensor IC’s – TSOP 1738. A couple of transistors and associated components complete
Multi-Tone Alarm This multi-tone alarm circuit will help you create a burglar alarm that will not only alert you of intruders but will also play a different tune each time an intruder comes, this makes sure that no regular intruders will have to listen to the same boring tone again and again! 🙂 Kidding aside this
Scream Generator Circuit Scream generating circuit? Well actually this is a simple sound generator circuit, but of course, you can create a screaming sound with it. It has unlimited possibilities in pranks and Halloween, just use your imagination. It works like a car horn or a doorbell but intensity increases the more you keep it pressed.
Super light Sensitive Intruder Alarm Circuit Intruder alarms are popular devices used in high-security areas as well as civilian houses to detect and alarm the presence of any intruders. There are different kinds of intruder detection alarms, some detect movements by using a laser, some use pressure variations etc. Our intruder alarm works using an
Doorbell Circuit Description Related Posts: Melody Generator using UM 66 Door Bell Circuit Using NE555 The main objective of the doorbell circuit is to convert electrical signals (input) into audio signals (output) with a single press of a switch. The circuit given below is a modified version of the Melody Generator Circuit, whose link
In this project, we’re building a simple Lamp Flasher circuit using NE 555. A lamp flasher is nothing but a lamp dimmer circuit – where the lamp is turned ON/OFF at set frequency or time intervals. We’ve designed this circuit using the most popular and common components like the NE/SE 555 IC. Let’s begin our
In this project guide, we’re building a Touch Switch Circuit using NE 555 IC. As you know, NE/SE 555 is a very popular timer IC with multiple applications in different projects. A touch switch is basically a simple switching circuit activated upon a touch. If you’re new to 555 IC, please take the time to
In this project, let’s learn about automatic wiper control using NE555 IC. As you all know, NE/SE 555 is one of the most common timer IC ever created in the world. There is absolutely no electronics enthusiast who has never played with the 555 IC. We’ve extensively covered 555 IC, where we have a big
Simple Radio Circuit Op-amp is the short form for Operation Amplifier. It is a device used to amplify voltage, and is very popular due to its high gain amplification. It can often amplify voltage to hundred times of what is input. This project is aimed at making a simple radio circuit using an opamp. Description
Power Supply Circuit-40 Volts-2A LM317 is a widely used linear voltage regulator. It has 3 pins; input, output and adjustment. LM317 are energy wasters and always require a heat sink to keep the temperature of the circuit low. But due to its simplicity LM317 find a place in a wide range of power supply units.
19 Watts Simple Amplifier Circuit This is a 19-watt simple amplifier circuit diagram using IC LA4440 from Sanyo. It uses very fewer components other than the IC LA4440. A very high-quality circuit with respect to its cost and ideal for beginners. Here IC LA 4440 is wired as a bridge amplifier to deliver a 19
InfraRed (IR) Sensor/Detector Circuit The IR circuit described below is mainly designed for liquid level detection or proximity detection. The IR sensors used here are an IR LED and an IR photo diode. The circuit operates by detecting the distance from the target by reflection of an infrared beam. The biggest advantage of this circuit is
This is the circuit diagram of a simple corrosion free water level indicator for home and industries. In fact, the level of any conductive non-corrosive liquids can be measured using this circuit. The circuit is based on 5 transistor switches. Each transistor is switched on to drive the corresponding LED when its base is supplied
The light dimmer circuit or fan regulator circuit (either case, the circuit, and design are the same, the only difference is the output load to be varied, that is, fan or light) is used to control the brightness of the light or the speed of the fan according to our desire. The objective of the
A fridge door open alarm circuit is explained with its detailed working and circuit. The objective of this circuit is to produce an audible alarm when the fridge is left open for more than a preset time. This versatile door alarm is made possible with the use of two 555 timer IC’s. Both the 555
In this article, we have designed a transistor-based security alarm circuit with a high power siren that can be used to provide security for homes or as a warning for intruders trespassing. Only the basic design is provided in the circuit. You can check for advanced security alarm circuits using Arduino and Micro-controllers in the
An Automatic LED Emergency Light circuit is designed to turn ON when there is no adequate lighting or if the power supply is cut-off. Earlier fluorescent lights were used to build such circuits. But the use of LEDs has proven to provide adequate lighting for a longer period before draining the battery. We have developed
All audio amplifiers have some mechanism to increase and decrease volume. Most such mechanisms involve mechanical parts like a potentiometer. Here this project is to create an audio controller that works digitally. This is a very simple project which uses two switches and an IC to electronically control the audio output from an amplifier. Digital
A simple electronic combination lock is designed using IC LS 7220. This circuit can be used to activate a relay for controlling (ON & OFF) any device when a preset combination of 4 digits are pressed. The circuit can be operated from 5V to 12V. The LS7220 IC is a MOS digital lock IC that
A simple “tone generator” is a cool circuit that everyone must build in their electronics learning process. We’ve designed this tone generator circuit using 8021 IC, two transistors (BC548 or C8050), a small speaker and some associated components. As you see, components are minimal and you don’t need to spend more than a small amount
In this project, let’s learn how to make a Simple Proximity Detector or Sensor circuit using minimal components. A proximity detector is a fun project with lots of interesting applications to be built with. You can make very useful applications like a burglar alarm, a visitor counter, a proximity-based switching application, etc. This is a
