Over Voltage Protector. Simple Design 9


This is one simplest form of Over voltage Protector for the Bread board power supply. Usually we use 12 volt DC power supply to power the bread board. If the CMOS devices are used in circuit assembly, over voltage can damge them permanatly. This circuit limits the voltage to the bread board to 12 volts. If the voltage increases above 12 volts due to a high voltage surge in the AC lines ,the circuit cut off the power to the bread board. It can also be used in any device like Chargers that works on 12 volt DC .
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Over Voltage Protector. Utility Gadgets .12

Protect your LCD TV from Over voltage. After a power failure or during lightening, very high voltage surge develops in the Mains line which is the major cause that damage TV. Plasma and LCD TV are costly devices and uses SMPS type power supply. Use of Stabilizer is recommended for LCD TV. This low cost circuit can do the job of protection very well. When the mains voltage increases above 250 volts, it will drop most of the voltage around 100 volts passing through the load and the condition remains as such till normal voltage level attains.

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Peak Hour Timer. Utility Gadgets.3

This is one of my most attracted Circuit published in Electronics for You Magazine September 2008 issue. The circuit is doing a great job. It automatically cut off the Fridge during the Peak hours from 6 pm to 9 pm saving lot of energy and money. After the peak hours, the Fridge will turn on automatically. Try it and  avoid the task of manually switching off the Fridge every day during peak hours.

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Timer Relay. Design Trick 16

You can make this Transistor timer easily for driving a relay for few seconds to few minutes. It is too simple and uses only two transistors and few other passive components. Just press on the switch to start relay and after the time ends, relay will switch off. You can also set the time using a Trimpot.

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