AM Radio Transmitter Board Short Wave Low Power Sound Amplification SW Radio Am

High Frequency Oscillation: 21MHZ high frequency oscillation, crystal Y1 in the circuit is a parallel resonance, equivalent to the inductor. Structure: Mainly consists of power input, sound amplification, sound modulation, 21MHZ high frequency oscillation, Class C high frequency amplification, 21MHZ low pass filter.

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