How An Fm Transmitter Works?

[fizikzede]

We need to explain the basic princples of an fm transmitter such as how its calculations done in which fm band(like 89.3) it broadcasts if any of you could explain us how the circuit below works and purpose of its elements im in your debt

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[colin55]

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[audioguru]

It is an extremely simple FM transmitter. Its perfrormance is horrible.

Q2 is a Colpitts oscillator. Look it up in your textbook or in Google.

The 2N2369 is its extremely old high frequency transistor that is obsolete. Tell your teacher that the largest electronics parts distributor in North America (and maybe in the world) does not have one.
Ask your teacher to teach about modern things.

The radio frequency depends on the LC tuned parts values, the value of the positive feedback capacitor C7, the capacitance of Q2, the supply voltage and the values of all the stray capacitances around the circuit. C4 is not needed.

The frequency also changes when something moves toward or away from the antenna because the tuned LC circuit is affected.

We assume that you were taught how a transistor is biased.