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      This is the schematic for an FM transmitter with 3 to 3.5 W output power that can be used between 90 and 110 MHz. Although the stability isn't so bad, a PLL can be used on this circuit. This is a circuit that I've build a few years ago for a friend, who used it in combination with the BLY88 amplifier to obtain 20 W output power. From the notes that I made at the original schematic, it worked fine with a SWR of 1 : 1.05 (quite normal at my place with my antenna). Circuit diagram   Parts: R1,R4,R14,R15 10K 1/4W Resistor R2,R3 22K 1/4W Resistor R5,R13 3.9K 1/4W Resistor R6,R11 680 Ohm 1/4W Resistor R7 150 Ohm 1/4W Resistor R8,R12 100 Ohm 1/4W Resistor R9 68 Ohm 1/4W Resistor R10 6.8K 1/4W Resistor C1 4.7pF Ceramic Disc Capacitor C2,C3,C4,C5,C7,C11,C12 100nF Ceramic Disc Capacitor C6,C9,C10 10nF Ceramic Disc Capacitor C8,C14 60pF Trimmer Capacitor C13 82pF Ceramic Disc Capacitor C15 27pF Ceramic Disc Capacitor C16 22pF Ceramic Disc Capacitor C17 10uF 2...

Features: Built−in Protector Circuits (for surge and thermal, etc.) Built−in Automatic Operating Point Stabilized Circuit Low Distortion, Low L/F Noise Small Transient Nosie at Power ON/OFF Switching Good Channel Separation Few External Components Pin connection: Dual Audio Power Amp 5.3W/Ch. NTE1371 Supply Voltage (Note 1), VCC . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20V Peak Supply Voltage (Note 2), VSURGE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40V Total Current, ICC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4A Power Dissipation (TA = +30°C), PD . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30W Operating Temperature, Topr . . . . . . . .  . . . . . . . . . . . . . . . . . . . . . . . . . . . . −30° to +75°C Storage Temperature Range, Tstg . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . −55° to +150°C