Long range uPD6121 IR Transmitter

Here is a long range Digital IR transmitter. It is a precision IR transmitter suitable for TSOP 1738 IR receiver module. Unlike other IR transmitters, this circuit is highly reliable and gives fail proof operation.

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Personal Alarm

If you feel threatened or need an urgent support in a crowd, use this alarm to catch the attention of others. It generates a loud siren simulating that of the Fire brigade which is enough to get support from others. A single press on the switch can activate the siren for 2 minutes and then it automatically stops. It is too small enough to keep in the pocket or hand bag.

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Bread board Regulated Power Supply

You can use this multi voltage power supply for the bread board projects. Most of the circuits require regulated power supply for errorless operation. This power supply can give regulated 12V, 9V, 6V and 5 V. Charger point for battery charging and Test point for LED and Buzzer are also included.

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Trick to detect Electronic Smog

Electrons are invisible to human eye then how can we see the electronic smog existing in our home. Is there any method to see them? Impossible, the only method is to capture the energy from it to activate a circuit for giving a visual indication. When you sit in front of a computer or television, you are being bombarded by harmful waves quietly emanating from it. Even if you turn off the device, your biomagnetic field is still bombarded 24 hours a day, 7 days a week by the EM radiations from power cables, electric and electronic instruments etc. These radiations of different frequencies exist in our environment as Electronic Smog. Extremely low frequencies waves (ELF) exist wherever electricity flows and radiate it from every electrical item in your environment. Let us try this circuit to give a visual indication of the electronic smog.

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Trick to See Infrared

Have you seen Infrared rays so far? It is difficult to see because it is beyond the spectral response of our eye. Our photosensitive cells in the retina detect only the visible light in the range 450-750 nm. But many animals can see infrared spectrum lying above 900nm.Then what we can do to check whether, the Infrared LED in our project is working or not. A Digital camera can solve the problem. See how it detects the infrared.

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Unusual LED Indicator

Here is an Unusual LED indicator for the Battery. It turns on fully when the battery voltage is above 13 volts and starts to blink faintly when the voltage drops below 12 volts .Finally the LED turns off  when the voltage drops below 10 volts. Its design is unusual because the LED driver transistor is connected in an unusual way.

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Definitely, Arduino has evolved as a phenomenon in electronics and this Open source prototyping platform has gained immense popularity in the field of electronics. Ever since its introduction in 2005, Arduino has gained much popularity in the electronics world due to its easy to use application properties. It is an extremely easy to use platform compared to other prototyping platforms and uses flexible hardware and software to create an interactive environment. Designers can use the libraries and reference designs to integrate Arduino into their projects.

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