Service Points - Hitachi 42HDF52A Service Manual

4. Service points

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
Remove all lead-free solder from soldered joints when replacing components.
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:
Soldering iron with temperature control function (temperature range: 320-450℃)
Recommended temperature range per part:
Part
Mounting (chips) on mounted PCB
Mounting (chips) on empty PCB
Chassis, metallic shield, etc.
(1) EMI PWB, AUDIO TRANSFER PWB, RS-232 PWB, AUDIO PWB, KEY PWB, IR PWB, I/O PWB,
CONNECTOR PWB, SPEAKER CONNECTOR PWB
(2) MAIN PWB
(3) ATSC BOX(Digital Tuner Module) / TUNER
(4) POWER PWB
(5) PDP MODULE (is all lead free solder. X-SUS PWB, Y-SUS PWB, LOGIC PWB, ADDRESS PWB, SDM PWB)
The PWB assembly which has used lead free solder
Soldering iron temperature
320℃±30℃
380℃±30℃
420℃±30℃
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