This needs no power supply. It is operated only by the voice power.
Audio power is translated for electric power and it excite radio frequency oscillator. And by the way, audio power modulates the radio frequency signal. 8cm speaker is used for the microphone. The audio signal is rectified by the diode (D1). C1 capacitor is charged for 2 volts by the big voice. Small voice adds the modulation signal upon the DC voltage. You must speak like “Waaaaaaaaaa this is jf1ozl Waaaaaaaaa cqcq”. This transmitter generates about 20 micro watts radio frequency energy. You can use it only the same room, between this transmitter and the radio
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