Service manual

44
DV-NC70U/C
DV-NC72U
FLOW CHART NO.18
2Only REC mode inoperative
YES
NO
NO
YES
YES
YES
NO
YES
NO
NO
YES YES
YES
NO
NO
YES
NO
NO
YES
YES
NO
Are REC and/or PB mode inoperative?
Check peripheral circuit of X701.
1Only PB mode inoperative
Does PB CTL signal appear at
pin(76) of IC701 (TP204)?
Does AA-MH harness normally?
Does A/C head operate normally?
Replace A/C head.
Check AC-MC connector and
capstan FG signal line.
Check capstan motor unit and/or
replace.
Is there capstan AFC and APC
at pins(31) and (33) of IC701?
Replace IC701.
Replace AA-MH harness.
Readjust the A/C head height.
Is there 14.3MHz oscillation at
pins(37) and (38) of IC701?
Does the capstan FG signal appear
at pin(67) of IC701?
Dose pin(29) of IC701 operate
normally?
Check 1.
Check 2.
Replace IC701.
Is there REC CTL signal output at
pins(74) and (75) of IC701?
Is the V-SYNC signal (reference)
at pin(50) of IC701?
Check peripheral circuit of
C715~716 and R708.
Is there capstan AFC and APC
at pins(31) and (33) of IC701?
Capstan servo does not function.
FLOW CHART NO.19
NO
YES
YES
NO
YES
NO
YES NO
YES
NO
NO
NO
NO
YES
YES
Is picture signal inputted into pins(28), (30) and
(31) of IC201?
Is picture signal outputted to the pin(52) of IC201?
Is picture signal inputted into the pin(49) of IC701?
Check the line between pin(52) of
IC201 and pin(49) of IC701.
Is 5V applied to the pin(12) of IC201?
Check the PC 5V line.
1 External input mode
• Check the line between the rear video input
terminal and pin(30) of IC201.
• Check the line between the rear video input
terminal and pin(28) of IC201.
2 U/V tuner mode
Check the line between the pin(24) of TU101
and pin(31) of IC201.
Is picture signal outputted to the pin(47) of IC701 ?
Is 5V applied to the pin(51) of IC701?
Check the V
DD
line of IC701.
Is picture signal outputted to the emitter of video
output buffer (Q251)?
Line output:
Is there V-SYNC signal input at pin(5) of IC2003?
Check the line between pins(62) and (63) of IC201
and pins(84) and (85) of IC701.
Check Q251 periphery.
NO
Check the line between the Q251 emitter and the
pin(5) of IC2003.
Is there V-SYNC signal output at pin(2) of IC2003?
YES
NO
Check the VIDEO OUT terminal (J1202) and the
line between the pin(2) of IC2003 and the VIDEO
OUT terminal (J1202).
YES
YES
Is the pin(1) of IC2003 on "L" level?
Replace IC2003.
NO
Check the DVD-(H) line.
NO
Is 5V applied to the pin(3) of IC2003?
Check the PC 5V line.
Are serial data and clock signal applied to the pins
(63) and (62) of IC201?
Picture E-E does not appear.