Normally, home appliances are controlled by means of switches, sensors, etc. However, physical contact with switches may be dangerous. The circuit [[wysiwyg_imageupload::]]described here requires no physical contact for operating the appliance. You just need to move your hand over the light dependent resistor (LDR). The device connected to it switches “on” when you put your hand over the LDR and remains “on” until you again move your hand over it.The circuit is based on two ICs: one is operational amplifier LM741 and JK Flip Flop CD4027. An op-amp produces an output voltage that is hundreds of thousand times larger than the voltage difference between its input terminals. CD4027 is a master slave JK flip flop IC which works in toggle mode. Here this IC can be used to change the state by the signal applied to one or more control inputs and will have one or two outputs. CD4027 has four inputs namely J, K, Set and Reset and it contain two outputs namely Q and Q bar (Q not).