Proximity detector circuit

admin February 14, 2012 9 Comments

NE567  tone decoder / PLL IC. NE567 is a tone decoder IC from Philips. The IC has a built in PLL circuit with AM lock detection and an output driver circuit. The main function of NE567 is to drive...
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Liquid level indicator

admin October 12, 2012 11 Comments

LM1830 based liquid level indicator circuit. LM1830 is a monolithic integrated circuit that can be used in liquid level indicator / control systems. Manufactured by National Semiconductors, the LM1830 can detect the presence or absence of polar fluids ....
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Digital compass circuit

john January 6, 2010 13 Comments

Description. Here is the circuit diagram of a very simple and accurate electronic compass using the 1490 digital compass from Dinsmore. The 1490 digital compass is a solid state Hall Effect device which is sensitive to detect the Earth’s...
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Temperature controlled LEDs

john August 18, 2009 23 Comments

Description. The circuit is nothing but two LEDs (D1 and D2), whose status are controlled by the temperature of the surroundings. The famous IC LM35 is used as the temperature sensor here. Output of LM35 increases by 10mV per...
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Zero degree Celsius alarm

john May 14, 2009 3 Comments

Description. This simple circuit will produce an alarm whenever the temperature falls below zero degree. A thermistor is used here to sense temperature. The op-amp LM7215 is used to compare the reference voltage and voltage from the thermistor network....
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VHF field strength meter

john April 15, 2009 9 Comments

Description. This is a simple and low cost wide band VHF field strength meter. The field strength is measured by converting the radio signal to DC and measuring it. The RF signal will be picked up by the coil...
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Electromagnetic field sensor circuit

john August 17, 2009 27 Comments

Notes. This is a very simple circuit that can be used to sense electromagnetic radiations. The circuit can even detect hidden wrings. A 1mH inductor is used for sensing the electric field. The electric field will induce a small...
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Single chip metal detector circuit

john January 18, 2011 39 Comments

Description. This is a simple single chip metal detector circuit based on IC CS209A from the Cherry Semiconductors. A 100uH coil is used to sense the presence of metal. The IC CS209A has a built in oscillator circuit and...
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Touch switch using CD4011.

john March 6, 2010 22 Comments

Description. A simple touch switch circuit using CD4011 is given here. The IC CD4011 is wires as a flip flop here. The 9, 13 pins of the IC works as the set and reset contacts respectively.CMOS ICs like 4011...
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Water Sensor Circuit with Alarm

john October 12, 2012 16 Comments

If you are looking for a Water level indicator or a Water level controller, there are pretty good circuits we have developed. This one is just a fun project made for hobby purpose! You can call this a water...
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