Wiring Schematic Diagram

20W RF FM amplifier circuit diagram

This Fm rf ability amplifier has 2 transistors from Philips : BLV 10 and BLW 87. The 2 rf transistors assignment in chic C and this fm amplifier has a absolute accretion of 21dB ( 100 X ) and ability 55 – 65%.

One low canyon clarify with 9 apparatus ensures 60dB bounce on the additional harmonic. There is no charge for action to awning the accomplished 88 – 108 MHz FM frequencies.

The heart of the circuit is 2SC1946A VHF RF power transistor. The transistor is specifically designed to operate at frequencies up to 175 MHz, with very good results.

The feedline is decoupled. The current amplifier can be more than 5 amps. All coils are made of 16gauge wire rod (copper or silver wire can do better) and HF RFC may be central torus (as shown in the image) or 6-hole ferrite R1 bead.C3 and snubber circuit forms, while R2 and C6 prevent the amplifier self-oscillation in VHF, it is sometimes necessary to add 180 ohms in parallel with the amplifier will L7.That to dispel UNDESIRABLE VHF thereby reduce the spurious level.

The 60Watts VHF power amplifier using the above circuit. 2SC1946A Two transistors are arranged at 90 degrees to each other and their results were combined using "Network Power Combiner". It is very difficult to combine skills in the VHF and UHF

Explore power amplifier integrated circuit from National Semiconductor LM4780. What's so special? Well, first of all - a very low harmonic distortion. In general, manufacturers indicate the maximum power of his ingenious craft regularly with the harmonic content of 10%. At the same chip, CT in the specified maximum power is only 0.5%! Therefore, it is the most honest of all mikruha've found.

The chip implements two identical amplifier channels and features are given for the stereo amplifier. Circuit can also operate in mono - the inclusion of the bridge. In this case, the power output at CT = 0.5% of 120 watts. Other features remain virtually unchanged.