2KM Long Range FM Radio Transmitter

This long-range FM radio transmitter has an additional RF power amplifier stage, after the oscillator stage. The extra RF power amplifier used to strenght up the power output to become 200-250 milliwatts. With a great matching multi-element Yagi antenna or 50-ohm ground—plane antenna, this transmitter can give great good signal strength up to a distance… Read More »

4 Stage FM Transmitter

This is the FM transmitter circuit which apply 4 radio frequency stages, that are a VHF oscillator designed around transistor BF494 (T1), a preamplifier designed around transistor BF200 (T2), a driver designed around transistor 2N2219 (T3) and also a power amplifier designed around transistor 2N3866 (T4). A condenser microphone is wired at the input of… Read More »

2 Transistor Mini FM Transmitter

This is a mini FM transmitter built and powered using 2 transistors, designed by Tony van Roon. This small transmitter is simple to build and its transmissions could be picked up on any common FM radio. It possesses a range of approximately 1/4-mile (400 meters) or even more, depending on the line-of-sight, obstructions by big… 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 »

15W FM RF Amplifier with 2SC2539

This is a 15W FM RF amplifier circuit which build based on RF Power Transistor 2SC2539. 2SC2539 is a silicon NPN epitaxial planar type transistor designed for RF power amplifiers in VHF band mobile radio applications. FM RF Amplifier Circuit Diagram: Coil Specifications: L1: 2T Coil diameter:4mm L2: in series 6pcs Toroidal ring L3: 4T… 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 »