Micro FM transmitter

The simplest circuit, very few components, can be used to carry children's toys or used by the NAND gate IC1 (74Ls13), microphone MIC1 and composed of four resistance and capacitance.
    Electret microphone bias voltage required by the power supply through R1. Microphone signal to IC1's ⑤ feet, FM signal output by ⑥ foot, firing into the air by the antenna. C2 to improve the role of the circuit sensitivity. C1 for the power supply decoupling capacitor, there's no rush on the pulse interference could inhibit out, use common short wire antenna.
    Firing frequency of about 100MHz (third harmonic), working in VHF FM band, with regular radio can receive FM waves. Emission signal coverage up to 20 meters.
    The circuit sensitivity, positive feedback occurs sometimes (especially when in your hand). Just place the transmitter on the right, will work properly.

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