This is a mini fm transmitter circuit. I think this is the simplest one. Simple, easy and of course… inexpensive… The supply voltage is between 1.1 – 3 Volts with power consumption is 1.8 mA at 1.5 Volts. This circuit should be able to cover 30 – 50 meters of range max. at 1.5 Volts.… Read More »
Here the simple and low cost FM transmitter which powered using two transistors. This circuit may be tuned to operate over the range 87-108MHz with a range of 20 or 30 metres. The circuit works with 9V power supply, use regulated power supply for better quality. The coil L1 was consist of 7 turns on… Read More »
This is a simple, well designed 1.5 Watt FM Transmitter circuit using power transistor 2N2219A. This circuit should be able to cover 1-2 KM range. It use +5-30V power supply to work. Refer to the above diagram, the input source is an electret condenser microphone (you may try to use other input sources) and signal… Read More »
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 »
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 »
Here is the circuit diagram of ultrasonic sensor switch. There are many methods of wireless switching such as by using infrared, AM/FM signal, bluetooth, etc. This is an alternate wireless switching by using ultrasonic sensor. The distance of switching range should be more than 10 meters. This circuit produces and transmits ultrasonic sound of frequency… Read More »