The oscillator shown generates a signal in the 4.5 MHz band and can be used for audio modulation of TV transmitters. Remember that the 4.5 MHz offset in relation to the video carrier is necessary to superimpose the audio signal to be transmitted together. The capacitors are all ceramic and the crystal can be of a multiple frequency of 4.5 MHz, such as 7.15122 MHz, found in old televisions. The L1 coil consists of 40 coils of wire 32 in the form of a 4 mm diameter with a ferrite core.
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