Hitachi 42HDS52A/DW1-UB, Service Manual

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8
DW1U
Information for service about lead-free solder introduction
Hitachi introduced lead-free solder to conserve the "Earth Environment".
Please refer to the following before servicing.
(1) Characteristic of lead-free solder
Melting point of lead free solder is 40-50 o C higher than solder containing lead.
(2) Solder for service
Following composition is recommended.
" Sn - 3.0Ag - 0.5Cu " , or " Sn - 0.7 Cu "
Lead solder can be used, but there is a possibility of failure due to insufficient strength of the solder.
Caution when using solder containing lead.
Please remove previous solder as much as possible from the soldering point.
When soldering, please perfectly melt the lead-free solder to mix well with the previous solder.
(3) Soldering iron for lead-free solder.
Melting point of lead-free solder is higher than solder containing lead.
Use of a soldering tool "with temperature control" and "with much thermal capacitance" is recommended.
(Recommended temperature control : 320
o
C - 450
o
C)
Recommended temperature
PWB with chip parts 320
o
C +/- 30
o
C
PWB without chip parts 380
o
C +/- 30
o
C
Chassis, metal, shield etc. 420
o C +/- 30 o C
(4) Identification of lead-free PWB
2003 models >> not applied
2003 models >> mixed
2004 models >> lead-free solder is introduced
2005 models >> lead-free solder apply
On lead-free PWB, "F" is added at the beginning of stamp on PWB. (e.g. F DW1)
6 GI