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 »

Three Stage 9V FM Transmitter

This circuit is a powerful three stage, 9V FM transmitter (Tx) with a range of up to 1 kilometer in the open. It uses an RF transistor in its output stage and two BC547″s for the first two stages. Distance of trans-mission is critically dependent on the operating Conditions (in a building or out on… Read More »

Active FM/AM/SW Radio Receiver Antenna

This is an active FM/AM/SW radio receiver antenna, can be used for FM radio receiver, AM radio receiver and SW (shortwave) radio receiver. This circuit use active component JFET VHF Amplifier MPF102 to boost the radio signal. It use 9VDC supply to work. On the shortwave band this active antenna is comparable to a 20… Read More »

15W FM Transmitter using BLY88C

This is long range FM transmitter with transmision power output is up to 15W. This 15W FM transmitter use power transistor BLY88C as the main transmitter amplifier. Building a good FM transmitter(88-110Mhz) begins with getting a good schematic. You don’t have to understand the precise working of the transmitter to build it. But some basic… Read More »

Mini FM Transmitter

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 »

Ultrasonic Sensor Switch

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 »