How to determine the current in X rated capacitors

High volt X rated capacitors are used to make Transformerless power supply. But the current delivering capacity of such power supply is very low generally less than 100 mA. Let us see how to select a Capacitor to get required current
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How to determine the voltage level in Lithium Ion battery

Lithium Ion batteries are now widely used in Mobile phones, Power banks, Digital cameras and other devices that requires 3.6 V . Lithium Ion batteries are long lasting since its current rating is very high above 2300 mAh.It is very important to maintain Lithium Ion batteries since, both over charging and poor charging may completely destroy the battery.Some have the habit of plugging the Mobile phone in charger overnight. Mobile battery needs to be charged only when its charge goes below 50 %.Proper charging and discharging increases the life of Mobile battery and its efficiency. Let us see its voltage levels
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How to retrieve data from the Laptop Hard Disk

Suppose the Laptop crashes and is irrecoverably damaged .Its Hard disk has full of valuable data. What will do to recover that? SATA to USB device will help. Its cost is just Rs.170 and available in Computer sellers. Open the small window on the back of laptop. You can see the Hard Disk there. Unplug from its socket. Connect it to the SATA-USB socket. Connect the USB cable to PC or Laptop. It will detect the removed Hard Disk. You can open the folders and copy the data. It can be a good external hard disk in future. Continue reading

Hacked LED Flood Light. Start Up Project 19

16AOnce I purchased a 10 watts LED Flood light for Rs. 450. The Ad was so attractive that it is capable of giving light similar to 40 watts Tube light with low current consumption. But the result was disappointing. So hacked it to see the power, current and voltage consumption. It is a 12Volt 10 Watts LED Flood light as mentioned in the pack. The result was very interesting. Nothing matches with theory, specification and real measurements. Generally, the 10 Watt White LED works on 12 V DC and requires 500 mA to 1 Amps current to get full brightness and Flood light effect. It has around 10V Forward voltage. It is usually powered by a high current LED driver that delivers 500 mA to 1 Amps current. Here comes the reality. Many LED flood lights use low current LED drivers or Capacitor power supply. LED Driver is a small SMPS with an output current rating. It must match with the current requirement of the LED. Cheap Capacitor power supply can give only 75 mA current per uF. So we purchase the lights by looking the specifications on the package and not realizing the actual condition of the light. To experiment with that Flood light, opened it to see what is happening inside.Secret revealed.
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Solar Day Light. Start Up Project 15

1Why use lights during day time to waste electricity? Sometimes we need it in some rooms. We can go for a “Green Solution” to harvest Solar energy for lighting an LED light during day time. Just fix a small Solar panel and a Strip LED. It needs no battery  because the solar panel itself acts as a battery. It generates DC voltage when the Photons of the Sunlight energize its semiconductor. So the light remains on throughout day time. You need only a 12V Solar panel and a Strip LED. Connect and relax. It will do its work for 20 years. No circuit is in it and you can easily connect it.
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Free Energy from Computer Fan. Start Up Project 11

6AIt is not a wonder but a real fact that, we can light a 3 V 1 Watt LED without any battery power. You can harvest that much “Free Energy” from a Computer cooling Fan that is resting in the Junk box. A Computer Fan generates around 1.5 Volts with a current of around 80 mA during its full speed rotation when coming close to a Table Fan. By adding a Joule Thief circuit, we can boost this 1.5V to around 4 volts. Well, that is a good idea. When the Computer Fan is close to a Table fan, the forcing wind from the Table Fan starts to rotate the Computer fan in its full speed. The 1.5V thus generating from the Computer fan appears in its connecting wires. Joule Thief takes this voltage and boosts it to 4V. It is sufficient to light a 3 V 1 Watt LED. The Computer Fan used in the project is an original one without any manipulation and not like the one found in some videos with a hidden battery. Let us see the “Free Energy Magic”. You can also name it as “Wind Power Project”.
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