Electronic Circuits

Described here is a simple electronic circuit which can be used in any test or quiz competition. Features of this circuit are:Whenever a switch is pressed, the  circuit locks the remaining three entries. It has a master reset switch which allows users to press the switch next time once they have pressed. It can be powered from variable power supply ranging from 5V to 15V.

Initially it may possible all or may two LED will be glowing for that you have to first clear the flip flop by pressing reset switch. Under this condition Q output of IC2 and IC1 become low.

Continue reading to find out assembling and working of the circuit with video.

With the help of this circuit you can control your home appliances without getting off from your bed. You have to just clap or puff in front of the microphone and  the device connected to it become "on" or "off". Features of this circuit are :- You can simultaneously "on" and "off" one, two or three devices.. You are not required to move from your place to "on" or "off" the devices.

When you clap in front of the Mic, clapping sound is converted into electrical energy by the microphone. These weak signals are then amplified by the transistor which acts as preamplifier. Sensitivity of the signals can be improved with the help of VR1. Now the transistor T1’s output is feed to monostable circuit which is wired NE555 IC. Whenever you clap in front of microphone, output pin 3 of IC1 goes high and this is fed to clock input of IC2 pin 14.