An emitter follower is non-inverting, hence the follow part. An oscillator is 0 degree phase for the feedback, approximately, as it depends on the gain and phase (margin).
I believe the phase shift is from C2 and C7, as that looks like feedback for a Colpitts oscillator, in conjunction with L11. That gives you a resonance of about 1.5 kHz. The 4.7 uF is to AC ground L11. The common emitter feedback is there to provide a high impedance buffer.
The bypass caps on the supply won’t actually do anything for an ideal voltage source, though maybe you have some resistance in the voltage source; I know LT Spice has that hidden in there.
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[ 2.7 ms ] story [ 14.1 ms ] threadAn emitter follower is non-inverting, hence the follow part. An oscillator is 0 degree phase for the feedback, approximately, as it depends on the gain and phase (margin).
I believe the phase shift is from C2 and C7, as that looks like feedback for a Colpitts oscillator, in conjunction with L11. That gives you a resonance of about 1.5 kHz. The 4.7 uF is to AC ground L11. The common emitter feedback is there to provide a high impedance buffer.
The bypass caps on the supply won’t actually do anything for an ideal voltage source, though maybe you have some resistance in the voltage source; I know LT Spice has that hidden in there.