Auto Muting Circuit During Phone Calls
Telephone conversation can be made disturbance-free using this simple circuit. As soon as you lift the telephone handset to converse, the TV, music system...
DIY Doorbell That Sounds Like a Parrot—No IC Required!
Here is a mains-operated door-bell that produces parrot-like sweet voice without requiring any musical IC. The circuit is cheap and easy to construct. The...
Circuit for UPS to Hybernate PC
Most of the low-power UPS systems available in the market do not have the facility to shut down the PC before they turn off...
DIY: Replace Fridge Bulb with Energy-Efficient LED Lighting
The incandescent lamp provided inside the refrigerators glows whenever we open the door. It suffers from several disadvantages like:
1. Being a single light source,...
DIY Reminder Circuit with Buzzer and LED
This easy-to-build electronic alarm will remind you of an impotant task after a preset time. It is particularly useful for housewives and busy professionals....
DIY Automatic Emergency Light Circuit with Auto Charging Feature
This emergency light has the following two advantages:
1. It turns on automatically when the mains power fails, so you need not search it in...
Simple Automatic Water-Level Controller
Water level controllers are common nowadays. The automatic water level controller described here is built around a timer NE555 and inverter buffer CMOS IC...
DIY LED Chaser Circuit with Tune Generator Using NE555
IC1 (NE555) is used here as a clock generator. It is configured as an astable multivibrator whose frequency can be adjusted with the help...
SHORT WAVE TRANSMITTER
This transmitter circuit operates in shortwave HF band (6 MHz to15 MHz), and can be used for shortrange communication and for educational purposes.
The circuit...
Protect Your Appliances with This Over/Under Voltage Cut-Out Circuit
This over/under voltage cut-out will save your costly electrical and electronic appliances from the adverse effects of very high and very low mains voltages.
The...