Lead acid battery charger circuit

admin January 21, 2014 188 Comments
Lead Acid Battery Charger Description Here is a lead acid battery charger circuit using IC LM 317.The IC here provides the correct charging voltage for the battery.A battery must be charged with 1/10 its Ah value.This charging circuit is...
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Audio Distortion Meter

admin February 23, 2011 1 Comment
Audio Distortion Meter Description Here is a simple 1KHz audio distortion meter that can measure the Total Harmonic Distortion (THD) on any load at any out put power.Here you have the option to select 2,4,8 or 16 Ohm loads....
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Audio Wattmeter Circuit

admin February 23, 2011 4 Comments
Audio Watt Meter Description This is an easy trick to measure the output of an amplifier.Here resistor R2 acts as the load for for the amp and it should be able to withstand twice the maximum power of the...
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Sensitive Intruder Alarm Circuit

admin November 18, 2011 67 Comments
Intruder Alarm Circuit Description Here is  the circuit diagram of an ultra sensitive intruder alarm. The shadow of an intruder passing few meters nearby the circuit is enough to trigger the alarm. Here IC2 uA 741 is wired as...
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Direct Coupled Radio

admin February 22, 2011 1 Comment
Direct Coupled Radio Circuit Description Here is the circuit of an excellent direct coupled radio ideal for listening to near by stations.The circuit uses Q1 as a diode detector and first audio amplifier.The detection is across the first emitter...
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Liquid Level Switch

admin October 12, 2012 9 Comments
Liquid Level Switch Description Here is a simple level switch circuit that switches on one relay and switches off another relay when the fluid level exceeds the set limit.This circuit is a modification of the Simple Water Level Indicator...
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DoorBell circuit using UM 66 IC

admin April 27, 2011 29 Comments
Doorbell Circuit Description Here is a simple and easy to build doorbell circuit using IC UM 66.The  details of UM 66  is given in the older post “Melody Generator using UM 66″. This is a slight modification of that...
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7 Segment Counter Circuit

admin April 27, 2011 60 Comments
Seven Segment Counter Display Circuit Description Here is the circuit diagram of a seven segment counter based on the counter IC CD 4033.This circuit can be used in conjunction with various circuits where a counter to display the progress ...
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Voltmeter circuit using LED

admin February 22, 2011 16 Comments
Car Battery Voltmeter Circuit Description This is a very useful circuit which when installed on your car gives the voltage of you car battery in a LED dot display form.The circuit is based on four comparators made of quad...
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Metal Detector Circuit

jacky July 25, 2018 42 Comments
Metal Detector Circuit I always wanted to make a metal detector seeing how cool it was in all Hollywood, Bollywood movies. One thing I realised is; things aren’t as difficult as you think it is. After all, I found...
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