5
DJM-850-K
5
6
7
8
5
6
7
8
A
B
C
D
E
F
1. SERVICE PRECAUTIONS
1.1 NOTES ON SOLDERING
1.2 NOTES ON REPLACING
1.3 NOTES ON SERVICING
• For environmental protection, lead-free solder is used on the printed circuit boards mounted in this unit.
Be sure to use lead-free solder and a soldering iron that can meet specifications for use with lead-free solders for repairs
accompanied by reworking of soldering.
• Compared with conventional eutectic solders, lead-free solders have higher melting points, by approximately 40 ºC.
Therefore, for lead-free soldering, the tip temperature of a soldering iron must be set to around 373 ºC in general, although
the temperature depends on the heat capacity of the PC board on which reworking is required and the weight of the tip of
the soldering iron.
Do NOT use a soldering iron whose tip temperature cannot be controlled.
Compared with eutectic solders, lead-free solders have higher bond strengths but slower wetting times and higher melting
temperatures (hard to melt/easy to harden).
The following lead-free solders are available as service parts:
• Parts numbers of lead-free solder:
GYP1006 1.0 in dia.
GYP1007 0.6 in dia.
GYP1008 0.3 in dia.
The part listed below is difficult to replace as a discrete component part.
W
hen the part listed in the table is defective, replace whole Assy.
Assy Name
PCB Assy Part No.
Parts that is Diffcult to Replace
Ref No.
Function
Part No.
Remarks
MAI
N
Assy
D
W
X3360
IC1405
13
V
→
3.3
V
DC/DC converter
BD932
8
EFJ
IC with heat-pad
IC140
8
13
V
→
1.2
V
DC/DC converter
BD932
8
EFJ
IC with heat-pad
IC2603
USB UCOM
ADSP-BF525BBCZ-5A
BGA
IC3007
FPGA
XC3S50A-4FTG256C
BGA
IC3201
DSP
D
8
10K013BZKB400
BGA
IC201
DAC
PCM1691DCA
IC with heat-pad
VOLTAGE MONITORING
This unit always monitors for power failure and will shut itself off immediately after an error is detected.
A power failure is indicated with flashing of the SETUP LED (Intervals: 250 ms [Lit 125 ms/Unlit 125 ms]).
All the LEDs other than SETUP LED will be unlit, and all the switches and
V
Rs will be disabled.
Repair the unit according to the diagnostic procedures described in “5.3 I
N
FORMATIO
N
O
N
PO
W
ER DIAGO
N
OSTICS.”
CONFIRMATION OF USER-SETTING
This product has user- and club-setting data. Be sure to confirm those data before starting repair, although changing them
may not have a large effect. Use the Check Sheet in “
8
.4,” to which you can transcribe the settings, as required.
The settings are stored in Flash ROM (IC2
8
02) on the MAI
N
Assy.
To display the [USER SETUP] screen, hold [SETUP (
W
AKE UP)] pressed for at least 1 sec.
To display the [CLUB SETUP] screen, press [PO
W
ER] (O
N
) while holding [SETUP (
W
AKE UP)] pressed.