Leeson feedback mechanism question

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The discussion centers on the creation of a feedback mechanism in a transistor circuit using noise amplification. Key questions include the location of feedback comparison in the provided topology and the impact of feedback at resonance when the phase is zero. The inductor, LSer, is identified as the feedback element that contributes to the circuit's negative-impedance stage, while the resonant circuit on the gate sets the operating frequency. There is speculation that the transistor's internal stray coupling may serve as the actual feedback source. The conversation invites further insights from a knowledgeable participant in the field.
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leeson mechanism reccomendation question
Hello,I want to created th following system.From the articles I see that we input noise to the amplifier then the noise gets amplified and we compare thefeedback from the output(s11) to the noise.
few questions:
1. where is the comparation of the feedback in the topology below.
I cant see here the feedback.
2. at resonance we have phase of 0,what is the effect of the feedback here?
Thanks.

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The inductor, LSer is the feedback element in making the transistor circuit a negative-impedance stage. The resonant circuit on the gate determines the frequency. Although unstated, I suspect that the actual feedback is the transistor's internal stray coupling. This is based on my reading of pgs. 2 thru 4 of your attached PDF file.

This is way outside my usual field so this reference will page @berkeman, who I believe is a ham radio operator that may have a better (and more accurate!) explanation.

Cheers,
Tom
 

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