Sharp HT-M700H Service Manual page 3

[2] Important service notes (For U.K. only)
Before returning the unit to the customer after completion of a
repair or adjustment it is necessary for the following withstand
voltage test to be applied to ensure the unit is safe for the cus-
tomer to use.
Setting of Withstanding Voltage Tester and set.
Set name
Withstanding Voltage Tester
Test voltage
Set time
Set current (Cutoff current)
Unit
Judgment
OK: The "GOOD" lamp lights.
NG: The "NG" lamp lights and the buzzer sounds.
PRECAUTIONS FOR USING LEAD-FREE SOLDER
1. Employing lead-free solder
"All PWBs" of this model employs lead-free solder. The LF symbol indicates lead-free solder, and is attached on the PWBs and service manuals. The
alphabetical character following LF shows the type of lead-free solder.
Example:
2. Using lead-free wire solder
When fixing the PWB soldered with the lead-free solder, apply lead-free wire solder. Repairing with conventional lead wire solder may cause damage
or accident due to cracks.
As the melting point of lead-free solder (Sn-Ag-Cu) is higher than the lead wire solder by 40 °C, we recommend you to use a dedicated soldering bit,
if you are not familiar with how to obtain lead-free wire solder or soldering bit, contact our service station or service branch in your area.
3. Soldering
As the melting point of lead-free solder (Sn-Ag-Cu) is about 220 °C which is higher than the conventional lead solder by 40 °C, and as it has poor
solder wettability, you may be apt to keep the soldering bit in contact with the PWB for extended period of time. However, Since the land may be
peeled off or the maximum heat-resistance temperature of parts may be exceeded, remove the bit from the PWB as soon as you confirm the steady
soldering condition.
Lead-free solder contains more tin, and the end of the soldering bit may be easily corrected. Make sure to turn on and off the power of the bit as
required.
If a different type of solder stays on the tip of the soldering bit, it is alloyed with lead-free solder. Clean the bit after every use of it.
When the tip of the soldering bit is blackened during use, file it with steel wool or fine sandpaper.
Be careful when replacing parts with polarity indication on the PWB silk.
Lead-free wire solder for servicing
Ref No. Parts No.
PWB-A DCEKSV594SJ03
PWB-B DCYONV594SJ01
PWB-C DCEKAV594SJ03
PWB-D DCEKMV594SJ03
PWB-E DCYOLV594SJ01
set value
4.7 kV DC
3 secs
3 mA
Indicates lead-free solder of tin, silver and copper.
Decode
Display
Power
Speaker Terminal
Tuner/SCART/Remote Control/Headphones/Motor Driver/Motor Control/Motor
WITHSTANDING
VOLTAGE TESTER
AC
OUT
SHORT-CIRCUIT
AC POWER
SUPPLY CORD
Description
– ii –
HT-M700H
PROBE
UNIT
CONNECT THE PROBE
TO GND OF CHASSIS
SCREW