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It is a terrible circuit.
Its preamp transistor is not biased correctly so might be saturated or cutoff which makes it not work.
Its radio frequency could be anywhere and might not be in the FM broadcast band.
This circuit is a simple two transistor (2N2222) FM transmitter. No license is required for this transmitter according to FCC regulations regarding wireless microphones. If powered by a 9 volt battery and used with an antenna no longer than 12 inches, the transmitter will be within the FCC limits. The microphone is amplified by Q1. Q2, C5, and L1 form an oscillator that operates in the 80 to 130 MHz range. The oscillator is voltage controlled, so it is modulated by the audio signal that is applied to the base of Q2. R6 limits the input to the RF section, and it's value can be adjusted as necessary to limit the volume of the input. L1 and C6 can be made with wire and a pencil. The inductor (L1) is made by winding two pieces of 24 gauge insulated wire, laid side by side, around a pencil six times. Remove the coil you have formed and unscrew the two coils apart from each other. One of these coils (the better looking of the two) will be used in the tank circuit, and the other can be used in the next one you build. The antenna (24 gauge wire) should be soldered to the coil you made, about 2 turns up from the bottom, on the transistor side, and should be 8-12 inches long. To make C6, take a 4 inch piece of 24 gauge insulated wire, bend it over double and, beginning 1/2" from the open end, twist the wire as if you were forming a rope. When
I don't know which circuit you built. If you made it on a breadboard then the high capacitance of all the wires and between all the conductive contacts make it not work. Make it on a compact pcb.
What is "capacitor 6"?
Most simple FM transmitters have a microphone preamp transistor, a Colpitts oscillator transistor and maybe an RF amplifier transistor. The Colpitts oscillator is a common-base transistor and the modulation at its base makes it conduct more and less. When it conducts more and less its capacitance changes that changes the frequency of the oscillator producing FM.
Your English is horrible.
You need to know simple arithmatic and Ohm's Law to see how the first transistor is biased.
R1 applies about 0.5mA to the JFET in the electret microphone.
The circuit is too simple:
1) Since the tuned circuit is connected to the antenna then the frequency will change if something moves toward the antenna or moves away.
2) Since it does not have a voltage regulator then the frequency will also change as the battery runs down.
3) It will sound awful without high audio frequencies because it does not have pre-emphasis like FM radio stations have.