Hitachi 32HDL52A, Service Manual

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10
4.Service points
z Lead-free solder
This product uses lead-free solder (unleaded) to help protect the environment. Please read these instructions
before attempting any soldering work.
Caution: Always wear safety glasses to prevent fumes or molten solder from getting into
the eyes. Lead-free solder can splatter at high temperatures (600
℃
).
„ Lead-free solder indicator
Printed circuit boards using lead-free solder are engraved with an "F."
„ Properties of lead-free solder
The melting point of lead-free solder is 40-50
℃
higher than leaded solder.
„ Servicing solder
Solder with an alloy composition of Sn-3.0Ag-0.5Cu or Sn-0.7Cu is recommended. Although servicing with
leaded solder is possible, there are a few precautions that have to be taken. (Not taking these precautions
may cause the solder to not harden properly, and lead to consequent malfunctions.)
Precautions when using leaded solder
z
Remove all lead-free solder from soldered joints when replacing components.
z
If leaded solder should be added to existing lead free joints, mix in the leaded solder thoroughly after the
lead-free solder has been completely melted (do not apply the soldering iron without solder).
„ Servicing soldering iron
A soldering iron with a temperature setting capability (temperature control function) is recommended.
The melting point of lead-free solder is higher than leaded solder. Use a soldering iron that maintains a high
stable temperature (large heat capacity), and that allows temperature adjustment according to the part being
serviced, to avoid poor servicing performance.
Recommended soldering iron:
z
Soldering iron with temperature control function (temperature range: 320-450
℃
)
Recommended temperature range per part:
Part Soldering iron temperature
Mounting (chips) on mounted PCB
320
℃
±30
℃
Mounting (chips) on empty PCB
380
℃
±30
℃
Chassis, metallic shield, etc.
420
℃
±30
℃
(1) IR PWB, KEY PWB, SW PWB, 2* I/O PWB
(2) MAIN PWB
(3) POWER BOARD
(4) HDMI BOARD
The PWB assembly which has used lead free solder