Wireless Car Alarm

This circuit is a wireless car alarm system that is built using two circuit modules, namely modules of transmitter and receiver modules. This circuit works on FM radio waves. Car alarms can be used on vehicles that have a 6-12VDC power supply. You can use the voltage stabilizer if your car power supply is too… Read More »

Car Alarm Simulator

This is a car alarm simulator which using the LED as a simulation output. This simple circuit can tell you whether your car is running or not by detecting the voltage difference when the car is on and off. This occurs because when your car is running the Alternator puts a out a voltage a… Read More »

250mW RF Power Amplifier

This is an 250mW RF power amplifier circuit project. This circuit is designed to amplify the output of about 7mW wide band FM transmitters to a final level of about 250mW. General purpose 12V DC power supply can be used to operate this RF amplifier circuit. Schematic Diagram: Components List: R1 ____________________ 10R R2 ____________________… Read More »

220V Light Dimmer

This simple 220V light dimmer circuit can be used to adjust the brightness of mains lights. It also can be used to adjust the speed of AC motors. It uses a triac, diac and has a radio-frequency interference (RFI) noise suppression circuit built into it as well. Schematic diagram: Components List: R1 = 10K R2… Read More »

Sound Activated Switch

This is a sound activated switch circuit. It’s will turn on and turn off based on a loud sound such as clapping your hands. You can adjust the sensitivity (how loud of a sound will activate the circuit) from a pin drop to a Mack Truck Horn. Very practical for a variety of projects. Add… Read More »

20W Bridge Amplifier using TDA7240A

This is a simple 20W bridge amplifier based on TDA7240A. This circuit is designed for car audio system, but you may use this circuit for your small home audio application… 🙂 . Schematic Diagram: This circuit operated with 18VDC asymmetrical power supply (positive (+) and ground only). Mount the power IC on a heatsink to… Read More »

2 x 70W Power Stereo Amplifier based on IC STA550

Here’s the circuit diagram of a 70W stereo power amplifier which built using single power IC STA550. The circuit is simple and require little additional electronic components to support the work of IC STA550. This power stereo amplifier works with dual polarity / symmetrical power supply. Since based to the datasheet, the negative supply range… Read More »

220V LED Flasher

This is a 220V LED flasher circuit which is intended as a reliable replacement to thermally-activated switches used for Christmas tree lamp-flashing. This a low cost circuit and easy to built since it only use little amount of electronic components.. Schematic diagram: Component Parts: R1_________ 100K R2,R5______ 1K R3,R6______ 470R R4_________ 12K C1_________ 1000F 25V… Read More »

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