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Sensors and Detectors

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Simple Dark Sensor Circuit with Buzzer

Last updated on 9 August 2025 by Admin-Lavi Leave a Comment

Simple Dark Sensor Circuit with Buzzer is a very easy project to make. It detect no light and makes sound. It is uses in night lights, security and alarms. Circuit works with LDR, 555 timer and buzzer. Low light makes buzzer ON. This circuit runs on 9V battery which is small and handy. Circuit Working: […]

Filed Under: Sensors and Detectors

Simple LED Alert for Telephone Off-Hook Detection Circuit

Last updated on 8 August 2025 by Admin-Lavi Leave a Comment

This Simple LED Alert for Telephone Off-Hook Detection Circuit shows when phone is in use by turning ON the LED. It checks voltage change when handset is lifted means off-hook. Circuit is good for old phones with no light alert. It is very useful for shared phones and stops call interruptions. Circuit runs on simple […]

Filed Under: LED and Lamps, Sensors and Detectors

Mobile Incoming Call Detector Circuit

Last updated on 13 August 2025 by Admin-Lavi Leave a Comment

Mobile Incoming Call Detector Circuit is smart project. Detect incoming call and make LED light up. Circuit is good for noisy places where ringtone is hard to hear. Catch RF signal from phone when call comes. Use LC circuit, transistor, 555 timer to turn ON LED. Circuit runs on 6V battery and is useful and […]

Filed Under: Sensors and Detectors

Metal Detector Circuit using IC CS209A

Last updated on 8 August 2025 by Admin-Lavi Leave a Comment

Metal Detector Circuit using IC CS209A is a cool tool to find metal near by. It is used for security, treasure hunt and in industries. This article shows simple but strong circuit using one chip called CS209A. It is easy to make and works great to detect metal. We can find metal from few inches […]

Filed Under: Sensors and Detectors

Simple 12V DC Fan Speed Controller Circuit

Last updated on 13 August 2025 by Admin-Lavi Leave a Comment

Simple 12V DC Fan Speed Controller Circuit is an useful project in electronics. It changes fan speed by adjusting the voltage. This post talks about fan speed controller using IC LM2941. LM2941 is low dropout voltage regulator and it handles up to 1A current. It is good for cooling, temperature control and automation projects. In […]

Filed Under: Sensors and Detectors

Simple Shock Sensor Alarm Circuit

Last updated on 6 August 2025 by Admin-Lavi Leave a Comment

In this Simple Shock Sensor Alarm Circuit we can feel vibration or shock, which then makes loud sound with piezo buzzer. This circuit is easy to make and can be used at home, in car and in many places. It is good for security, stop theft and in feel movement. Main parts of the circuit […]

Filed Under: Alarm Circuits, Sensors and Detectors

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