Wednesday, November 2, 2011

FM RF Amplifier 8 Watt based 2SC1971

FM RF Amplifier 8 Watt circuit diagram

The above design is very simple FM RF amplifier 8W Watt based 2SC1971 VHF power transistor. The RF Amplifier PCB layout designed for FM broadband 88-108 MHz transmitters using microstripline technique. This 8W RF amplifier circuit provides an appropriate power boost for transmitters with an input of 500 mW.

RF Amplifier PCB
The PCB outline is 77 x 56 mm use FR-4 double sided photoresist epoxy pcb material for best results.

RF Amplifier Construction
All SMD components are 1206 types. Connect the bottom layer (groundplane) on several points (through via's) with the top layer of the PCB.

CuL = magnetwire, enameled copper wire
- 1 mm equals approx. to #18 A.W.G
- 0.8 mm equals approx. to #20 A.W.G
- 0,3 mm equals approx. to #28 A.W.G.

All diameters are measured from the inside of the coils, i.e. 'internal' diameter.
Make sure to mount the rf-transistor on a appropriate heatsink and use some thermal heatsink compound between the flange of the transistor and heatsink! (Thermal resistance heatsink at least 6°C/W). All parts are soldered directly on the toplayer of the PCB.

FM RF Amplifier 8 Watt

FM RF Amplifier 8 Watt based 2SC1971, circuit diagram and PCB layout can be download from here

About RF Amplifier
An RF power amplifier is a type of electronic amplifier which is utilised to convert a low-power radio-frequency signal into a larger signal of significant power, usually for driving the antenna of a transmitter. It is usually optimized to have high efficiency, high output Power (P1dB) compression, good gain, good return loss on the input and output, and optimum heat dissipation.

The basic applications of the RF power amplifier include driving to another high power source, driving a transmitting antenna, microwave heating, and exciting resonant cavity structures. Among these applications, driving transmitter antennas is most well known.
More explanation about power audio amplifier can be found at
This is a demonstration about 01A RF Amplifier which is build used old tube component to amplify the signal.

Watch the video:

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