LG CED-8083B Service Manual page 25

BETA Measurement Circuit Check.
After inserting Test Disc
(TCD-784), 1x play.
IC401 Pin 86(RRF) : 3+/-1.0V?
YES
RRFIN: 2+/0.7V?
(IC401 PIN85)
YES
IC405 Pin 10 (CDR/RW) : 'H'?
YES
IC301 Pin 78(RFBETA) : 2+/-1.0V?
YES
Normal
66
NO
•
Check the connection of IC401 pin 86.
•
Check and replace the IC401(CXA2551R).
NO
•
Check the connection of IC407.
•
Check and replace the IC407.
NO
•
Check the connection of IC301 pin 20.
•
Check and replace the IC301(MICOM).
NO
Is BETA signal normal?
(IC405 pin 14)
YES
Check and replace the IC405(BU4052)
•
Check the connection of IC401
NO
pin 82.
•
Check and replace the IC401.