How to set the Re trigger Jumper in PIR sensor Module

The PIR sensor module has a Jumper arrangement to select single trigger and re trigger modes. Let us see how it works Continue reading


How to connect PIR sensor Module

It is important to know the connections of PIR sensor module. It is easy to connect it with alarms, relay to drive AC load etc. Let us see Continue reading

How to Convert SMPS to Bench Power supply cum charger

Don’t throw away the SMPS power supply when the Computer damges. SMPS is a high current device that gives different regulated voltages from the output wires. It has numerous wires to give different voltages . So you can make a good Multi voltage power supply for the Projects or use as battery charger for different types of batteries. It has total isolation from Mains and output is safe DC.
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Power Supply Box

This Power supply box can be used to interface with the High current Bench power supply made from the SMPS of Computer. The Power supply box has a DC-DC Converter cum Booster module, A Volt Meter and an Ammeter to show output voltage and current consumed by the load. Continue reading

Deterrent Light. Application Circuit 1

Install this Deterrent Light in your Home backyard and Porch to thwart the attempt of Burglary. This PIR Motion Sensor based light switches on instantly when it detects a Human movement from a distance of ten meters. The light turns on for 3 minutes and then turns off. It Re triggers again if the movement continues. Relay is used to drive the load, so any kind of lights can be used.
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Laptop Battery Power supply. Start Up Project 38

12ADon’t throw away old Laptop battery; it can be reused for other purposes. I hacked one Laptop battery and salvaged six high efficient Samsung Lithium Ion batteries each rated 3.6V, 4300 mAh. It is worth Rs. 1000. Few days before, I found that, my Laptop is not getting enough back up and shutdown immediately when the charger is removed. So I replaced the battery at the cost of Rs.1200. Due to curiosity, I just opened the case of the old battery pack and found that, the batteries inside can be reused. After testing, I found that only one battery out of the six is damaged. All the other five are in good condition. That damaged battery created the problem in the battery pack and prevented the remaining five batteries from their work. So actually this is happening in our Laptop. If one battery fails, we have to replace the battery pack. If the good batteries are salvaged from the old pack, we can reuse them for many different applications like LED lighting, Mobile charging, making power supply etc. So I spend Rs.1200 for the new battery pack but I salvaged 5 good batteries worth Rs. 1000 from the old battery pack. So my actual expense is only Rs.200. So do not discard the old Laptop battery. Tear it, salvage the individual batteries and reuse. You can save money and can reduce the e-waste.
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Peltier Joule Thief. Start Up Project 37

13AYou know, we can light a 1 watt LED without a battery! Peltier will give “Free Electricity” for that. When we heat the Peltier with flame, hot water or a hot object, it starts to generate current. Its voltage can be around 1.5V when the heat is above 60 degree. But this 1.5V is not sufficient to light even an ordinary LED that requires 1.8V minimum. 1 watt White LED requires 3.6V. Then how? We can add a Joule Thief circuit for that. A Joule Thief circuit is a self oscillating circuit that increases the input voltage as low as 700 mV to 4-5V. So if the Peltier is connected to a Joule Thief and heated, Joule thief will amplify the voltage to light the 1 watt LED. Let us check this.
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