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The 30 watt amplifier schematic shown below provides an appropriate power boost with an input of 4 watt up to 6 watts. The circuit is designed to cover 88-108MHz FM Broadcast Band. However, the circuit is very stable at my place and provides a clean-output through seven (7) element Butter-worth low-pass filter. Circuit Diagram: Notes: The heart of the circuit is 2SC1946A VHF RF power transistor. The transistor is specifically designed for operation in frequencies up to 175 MHz, with very good results. As you can see, the power line is well decoupled. The amplifier current can be over 5 amps. All the coils are made from 16gauge laminated wire (or Silver copper wire can do best) and the RFC can be of HF toroid core (as shown in the picture) or 6 holes ferrite bead.C3 and R1 forms snubber circuit while R2 and C6 prevent the amplifier from self-oscillation at VHF, sometimes you need to add 180 ohms in parallel with L7.That will cause the amplifier to dissipate UNDESIRABLE VHF thereby r...

This electronic circuit is a simple VHF FM transmitter circuit. The circuit can easily make portable use for a small 9 volt battery. Transmitter range from 60 to 100 meters range.  The construction of the circuit is very simple. Electrically adjustable frequency between 88 and 108MHz. Portable and low power consumption. You can use any FM receiver. 9 Volt works. Portable and Low Power VHF FM Transmitter Circuit Diagram Parts list: R1 = 10K R2 = 15K R3 = 3.3K R4 = 470 ohm R5 = 100K R6 = 4.7K VR 1 = 10K Pot meters VALUE C1 = 0.1uF----- 104 C2 = 0.001uF---- 102 C3 = 0.0015uF---- 152 C4 = 10pF ----- 10 C5 = 3pfF ----- 3 C6 = 2.5pF----- 2.5 C7 = 10pF ----- 10 C8 = 0.01uF---- 103 C9 = 0.022uF----- 223 C10 = 1pF ----- 1 C11 = 0.001uF---- 102