NAD C660 Service Manual page 19

Focus Servo is unstable
Is FE signal
output normal in Focusing
Up/Down? (IC108
pin 56)
YES
Is FAO signal
output normal in Focusing
Up/Down? (IC301
pin 207)
Go to "Focus Actuator operating
is abnormal"
Track Servo is unstable
Is TE signal
output normal in Focusing ON
and Tracking OFF?
(IC108 pin57)
YES
Is TE signal
input normal in Focusing
ON and Tracking OFF?
(IC301 pin198)
YES
Is
there TAO signal
output in Tracking ON?
(IC301 pin 208)
YES
Check the Driver
IC(IC203(BA5983)) and P/U refer-
ring to "Focus Actuator operating
is abnormal."
NO
Check the IC108 (CXA2551R).
Go to "RF output is abnormal"
NO
Replace the IC301 (OTI-9790).
Is PICK UP (E,F,G,H)
NO
output normal? (PN101
pin 16,7,13,10)
YES
Check the IC108 (CXA2551R).
YES
Go to "RF output is abnormal"
NO
Check the IC104 (NJM3403)
NO
Replace the IC301 (OTI-9790).
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NO
•Check the PICK UP FFC.
•Replace the PICK UP.