This simple tube FM radio uses a 12EC8 dual (triode-pentode) tube to receive signals and provide headphone listening. The coil consists of 6 turns of wire 28 in a 1 cm shape with sockets on turns 2 and 4. The antenna must be of the telescopic type and the tuning capacitor can be obtained on a disused FM radio. A feature of this circuit is its operation with symmetrical 12 V source, not requiring high voltage. The same source provides the filament voltage to the valves. The transformer is the driver type found on older tube radios, but a low voltage type of transistor radios can be tried. For RF shock wrap 20 to 25 turns of 30 to 32 wire in a 1 M x ½ W resistor.
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