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Has anyone thought what that portion of the circuit is doing? It looks weird to me.
It looks like a feeble attempt at providing further AM limiting. The plate of the limiter is capacitively coupled to the 19T8 diode plate. The choke coil is simply an RF choke to preventing the sound IF being bypassed fully to ground.
It looks as if this is an attempt to further IF limit any residual AM reached the sound detector. I am especially curious the placement of the 10uF electrolytic: the IF rectification of the diode should place a negative voltage on the diode plate corresponding to the peak negative excursion of the IF signal. This means the 10uF capacitor is reverse polarized.
Makes me think that it would work better if that coil was open!
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