This two tone siren circuit explained here gives out a continuously varying high amplitude sound. Since the supply voltage is not critical, it can be used in cars, motor cycles or at home. It can replace the ordinary call bell. A dual one siren is an amplified alarm circuit designed to generate two different audio tones resembling […]
Archives for 2011
Automatic Voltage Stabilizer Circuit for TV sets and Refrigerator
Here we will study the design of a simple automatic mains AC voltage stabilizer which can be applied for safeguarding appliances like TV and refrigerators from fluctuating voltages. A voltage stabilizer is a device which is designed to sense inappropriate voltage fluctuations in AC mains supply inputs, and correct them to produce a stabilized voltage for the […]
Simple Peltier Refrigerator Circuit
In this post I have explained a straightforward procedure for building a simple refrigerator using Peltier device for generating the required cooling effect inside the fridge. How Peltier Device Works We are all familiar with a Peltier device and know how it functions. A Peltier device is a 2-wire semiconductor device having two surfaces that […]
AC 220V/120V Mains Surge Protector Circuits
Voltage spikes can sometimes be a big nuisance as far as the safety of the various electronic appliances are concerned. I have explained how to make a simple AC Mains surge protector circuits at home. What is a Surge Protector A surge protector is an electrical device which is designed to neutralize minor electrical spikes […]
How to Configure a Solar Panel System – Living of the Grid
In thi post I have explained how to connect and integrate readymade solar panel system with our home, without depending on technical personnel or experts. The main gadgets required for implementing this are: a solar panel, a solar controller, battery and an inverter Introduction It’s been there since the earth was born and it is […]
How to Use LM317 for Making a Variable Power Supply Circuit
In this post I will elaborately explain how to build a simple LM317 based adjustable power supply circuit using minimum number of external components. As the name suggests a variable power supply circuit provides the user with a range of linearly varying output voltages through a manually controlled potentiometer rotation. A LM317 is a versatile […]





