Harman Kardon FL8550 Service Manual page 30

FL8550
5. MIRROR CIRCUIT
After RF input signal is amplified by Mirror amp, it is held in Bottom and Peak hold circuit. Such a hold is
determined by the time constant. Envelope signal A (demodulated to DC) is two-thirds of the peak value
of this signal. The time constant of A signal is held when it is larger than that of B signal. Therefore,
mirror output is; Low at track on disc, High at between tracks on disc, High when defect is detected.
6. DEFECT CIRCUIT
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