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#1

I'm having trouble with the analysis of this circuit

I understand (going from left to right) C1 takes the DC decoupled voltage from the Microphone, amplifies this via Q1, C2 decouples it again, then R6 and C3 Low Pass Filter it, but once we get to Q2, I am completly lost.

My question is: How does this circuit act as a colpitt FM oscillator. Most of them I've seen are directly attached to the base.

Secondly how does this circut actually accomplish frequency modulation: Please use math on me!!! (I know that it should change the delta F term in the equation cos(2*pi*fc*t + δF) to achieve FM, or more correctly: cos(2*pi*fc*t + δf*∫(messageSignal))

How can I determine the Frequency deviation of this circuit?

Please use Engineering terminology and Mathematical equations in your analysis: Im a Senior year EE.

I understand (going from left to right) C1 takes the DC decoupled voltage from the Microphone, amplifies this via Q1, C2 decouples it again, then R6 and C3 Low Pass Filter it, but once we get to Q2, I am completly lost.

My question is: How does this circuit act as a colpitt FM oscillator. Most of them I've seen are directly attached to the base.

Secondly how does this circut actually accomplish frequency modulation: Please use math on me!!! (I know that it should change the delta F term in the equation cos(2*pi*fc*t + δF) to achieve FM, or more correctly: cos(2*pi*fc*t + δf*∫(messageSignal))

How can I determine the Frequency deviation of this circuit?

Please use Engineering terminology and Mathematical equations in your analysis: Im a Senior year EE.