Category Archives: Radio



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 »

UHF TV Antenna Booster

This is the circuit diagram of UHF band TV antenna booster with 15dB gain power. This low cost antenna booster is simple and easy to build.It use single transistor BF180 to boost te UHF signal. Since this is an active circuit of UHF TV antenna booster, it will require a 12v power supply to operate.… 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 »

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 »