Sharp AM-900 Service Manual page 104

AM-900U
15
FAX communication
failure
16
Buzzer / Ringer
failure
TX/RX failure
Communication Speed
abnormal
Not sound
Volume not change
5 – 31
IC1 (Main CPU)
IC18 (Modem)
IC19 (OP AMP)
CNLIU
connector
F4 (fuse)
C,R on route of
IC1~IC18 & CNLIU
C,R on route of
IC18~IC19~CNLIU
Power line
+24VH, +5VA
IC18 (Modem)
IC19 (OP AMP)
C, R on route of
IC18~IC19~CNLIU
IC1 (Main CPU)
IC16 (Analog Switch)
IC17 (Speaker AMP)
CNSP
connector
C,R on route of
IC1~IC16~IC17
C,R on route of
IC17~CNSP
IC1 (Main CPU)
Q10/Q11/Q12 (Tr)
C, R on route of
IC1~Q10/11/12~IC17