VSX-LX50
68
1
2
3
4
1
2
3
4
C
D
F
A
B
E
Step 4: Audio
O
ut c
h
eck
Is there
a SPDIF
signal
?
Operation of IC701 is OK.
To STEP 4
Check the output from
IC701 (pin 105).
Yes
No
Yes
D+ and D- should have
waveform during normal
condition.
Check the pattern in the path.
Check the MOTHER Assy.
Are
there the waveforms
like figure?
Yes
No
IC701 (pin 105)
SPDIF
CN701 (pins 2,3)
D+/D-
Fig. D+
X: 1
μ
sec/div, Y: 2 V/div
X: 1
μ
sec/div, Y: 2 V/div
Fig. D-
Is there
a SPDIF
signal
?
Check the output from
IC701 (pin 105).
Yes
No
IC741 (pin 2)
SPDIF
Check the parts and
pattern between IC701
and CN702.
Are there
audio signal
?
Replace IC741.
Yes
No
IC741 (pin 4)
SPDIF
B
Step 4: Audio
O
ut c
h
eck
Is there
a SPDIF
signal
?
Operation of IC701 is OK.
To STEP 4
Check the output from
IC701 (pin 105).
Yes
No
Yes
D+ and D- should have
waveform during normal
condition.
Check the pattern in the path.
Check the MOTHER Assy.
Are
there the waveforms
like figure?
Yes
No
IC701 (pin 105)
SPDIF
CN701 (pins 2,3)
D+/D-
Fig. D+
X: 1
μ
sec/div, Y: 2 V/div
X: 1
μ
sec/div, Y: 2 V/div
Fig. D-
Is there
a SPDIF
signal
?
Check the output from
IC701 (pin 105).
Yes
No
IC741 (pin 2)
SPDIF
Check the parts and
pattern between IC701
and CN702.
Are there
audio signal
?
Replace IC741.
Yes
No
IC741 (pin 4)
SPDIF
B