Category Archives: Sensor



Remote Control Tester

Here is the remote control tester circuit. This circuit is really a simple and easy tester for verifying the basic operations of an infrared remote control unit. It is low-cost and very easy to construct. The tester is designed around infrared receiver module TSOP1738. Operation of the remote control is identified by a tone from… Read More »

Color Sensor

This is the color sensor circuit diagram. Color sensor is definitely an exciting project for hobbyists. The circuit can sense eight colors, i.e. blue, green and red (primary colors); magenta, yellow and cyan (secondary colors); and black and white. The circuit is based on the fundamentals of optics and digital electronics. The object whose color… Read More »

Heat Detector + Siren

This is the diagram of heat detector circuit which already integrated with siren circuit in the output. This circuit applies a complementary pair comprising NPN metallic transistor T1 (BC109) and PNP germanium transistor T2 (AC188) to detect heat (because of outbreak of fire, for example) in the area and activate a siren/alarm. The collector of… Read More »

Pyroelectric Fire Alarm System

This is definitely an ultra-sensitive fire sensor that exploits the direct piezoelectric property of an ordinary piezo component to recognize the fire. The lead zirconate titanate crystals within the piezo component have the property to deform and produce an electrical potential when heated, thus converting the piezo component into a heat sensor. The circuit mentioned… Read More »

Automatic Light Controller

This is the circuit diagram of automatic light controller which use 78xx voltage regulator IC series. The voltage regulator ICs deliver a constant output voltage, as against a extensively fluctuating input supply, when the common terminal is grounded. Any voltage about zero volt (ground) interconnected within the common terminal is added to the output voltage.… Read More »

Toy Car Remote Control

The circuit, consisting of an infrared transmitter-receiver pair, utilizes IR beam transmission to switch the toy car “on” or “off’, yeah… it will be only switching on and switching off, you may modify this circuit to make the toy car to turn left or right. To operate the toy car, you have to hold the… Read More »