28
DJM-850-K
1
2
3
4
A
B
C
D
E
F
1
2
3
4
[Checking the MUTE]
Check that the MUTE signal is within
the range of approx. –14 to –15
V
.
1-7
8
1-79
1-
8
0
1-
8
1
1-
8
2
1-
8
3
1-
8
4
1-
8
5
1-
8
6
1-
8
7
1-
8
7 1-
88
1-
8
9 1-90
1-
88
1-
8
9
1-90
1-
8
4
1-79
1-
8
1 1-
8
2 1-
8
3
1-7
8
5
Loose connection
/defective parts
MAI
N
Assy
IC1001
pin 9, 10, 11, 12
[Checking the DAC]
Check the output signal of DAC (IC1001).
• If the DAC output signal is normal, check the
conduction at C
N
3 and C
N
1005.
• If no DAC signal is found, go to [6].
10.35
W
A
V
EFORMS
6
Loose connection
/defective parts
MAI
N
Assy
IC1001 pin 3
[Checking the DAC]
Check the input signal of DAC.
• If no signal is found, DSP (IC3201) must be
improperly soldered or defective.
• If signal is found, go to [7].
10.35
W
A
V
EFORMS
8
Loose connection
/defective parts
MAI
N
Assy
96k CLK: IC1001 pin 4
6M CLK: IC1001 pin 2
24M CLK: IC1001 pin 1
[Checking the DAC]
Check the CLK signal of DAC.
• If no signal is found, go to 2-2 [6].
• If CLK signal is found, DAC (IC1001) must be
improperly soldered or defective.
10.35
W
A
V
EFORMS
7
Loose connection
/defective parts
MAI
N
Assy
IC1001 pin 5
[Checking the DAC]
Check the RESET signal of DAC.
• If it is H, go to [
8
].
• If it is H, go to 2-2 [5].
—————
1
Loose connection
/defective parts
MAI
N
Assy
IC3405 pin 16
Check for the signal at Pins 16 of DIT
(IC3405).
• If the signal can be found, soldering of any
part in the signal path from IC3405 to JA3401
may be defective. Check the soldering status.
If soldering is OK, replace the defective part.
• If no signal is found, go to [2].
10.35
W
A
V
EFORMS
2
Loose connection
/defective parts
MAI
N
Assy
C3411
Check for the
V
+3R3D_DIT power.
• If
V
+3R3D_DIT power is found, go to [3].
• If
V
+3R3D_DIT power cannot be found,
soldering of any part in the power path may be
defective. Check the soldering status. If
soldering is OK, replace the defective part.
4.4 PO
W
ER
BLOCK DIAGRAM
5.3 I
N
FORMATIO
N
O
N
PO
W
ER
DIAG
N
OSTICS
3
Loose connection
/defective parts
MAI
N
Assy
R3434
Check that the DIT_RESET signal level
is High.
• If it is H, go to [4].
• If the signal level is L, soldering of any part in
the DIT_RESET path may be defective. Check
the soldering status. If soldering is OK, replace
the defective part.
—————
4
Loose connection
/defective parts
MAI
N
Assy
IC3405
FPGASRC_LRCK
pin 24
FPGASRC_BCK
pin 26
ADAT_DOUT_FPGASRC
pin 2
8
FPGASRC_MCLK
pin 30
Check for the any signals of DIT
(IC3405).
• If any signal is abnormal, soldering of any part
in the signal path may be defective. Check the
soldering status. If soldering is OK, replace the
defective
part.
• If all signals are normal, soldering of the DIT
(IC3405) or the IC itself may be defective.
Check the soldering status. If soldering is OK,
replace the defective part.
10.35
W
A
V
EFORMS
[3-4] No signal is output from the DIGITAL MASTER OUT connector.
4-1
4-2
4-2
4-1
1
Loose connection
/defective parts
MAI
N
Assy /
SEC/HP Assy /
HPJK Assy
Check for the connection between the
MAI
N
Assy, SEC/HP Assy and
HPJK Assy.
Correct any power connections.
—————
2
Loose connection
/defective parts
SEC/HP Assy
C
N
101 pin 1, pin 4
Check for the signals at Pins 1 and 4 of
C
N
101.
• If a signal is found, the HPJK Assy or wires
are defective. Replace them.
• If no signal is found, go to [3].
10.35
W
A
V
EFORMS
3
Loose connection
/defective parts
SEC/HP Assy
HP_L+/L-
HP_R+/R-
Check the audio signal of SEC/HP Assy.
• Check for a part where the signal is interrupted,
by observing the audio signal before and after
each block. Soldering of the part or the part itself
where the signal is interrupted is defective. Or the
MUTE circuit is activated.
• If the MUTE circuited is activated, go to [4].
• If no signal is found at C
N
3, go to [5].
—————
4
Loose connection
/defective parts
SEC/HP Assy
MUTE
• If the signal is within the range of approx. –14 to
–15
V
, soldering of the MUTE transistors (Q103,
Q104) or any part in their peripheral circuits is
defective or one or more of those parts is defective.
• If the signal is outside the range of approx. –14 to
–15
V
, check the conduction at C
N
3 and C
N
1005
and check the above-mentioned MUTE
transistors. If they are OK, go to 3-1 [17].
—————
[3-3] No signal is output from the PHONES connector.
0
Prior
Confirmation
CUE button / LE
V
EL
knob / MIXI
N
G knob
/ MO
N
O, STEREO
selector
Confirm on the screen that the selector
is set properly.
—————
Operating
instructions
No.
Cause
Diagnostics Point
Item to be Checked
Corrective Action
Reference
No.
Cause
Diagnostics Point
Item to be Checked
Corrective Action
Reference