SYMPHONIC ST419B
Service Manual

With Soldering Iron: (1) Using desoldering braid, remove the solder from all pins of the flat pack-IC. When you use solder flux which is applied to all pins of the flat pack-IC, you can remove it easily. (Fig. S-1-3)

soldering iron to center of the flat pack-IC and heat up. Then remove (glue will be melted). (Fig. S-1-6) (5) Release the flat pack-IC from the CBA using tweezers. (Fig. S-1-6) Note: When using a soldering iron, care must be taken to ensure that the flat pack-IC is not being held by glue. When the flat pack-IC is removed from the CBA, handle it gently because it may be damaged if force is applied.

Flat Pack-IC

Desoldering Braid

Hot Air Blower
Soldering Iron
Fig. S-1-3

or
(2) Lift each lead of the flat pack-IC upward one by one, using a sharp pin or wire to which solder will not adhere (iron wire). When heating the pins, use a fine tip soldering iron or a hot air desoldering machine. (Fig. S-1-4)

Iron Wire

Soldering Iron To Solid Mounting Point
Fig. S-1-5

Sharp Pin
CBA Fine Tip Soldeing Iron

Fine Tip Soldering Iron

Fig. S-1-4

(3) Bottom of the flat pack-IC is fixed with glue to the CBA; when removing entire flat pack-IC, first apply soldering iron to center of the flat pack-IC and heat up. Then remove (glue will be melted). (Fig. S-1-6) (4) Release the flat pack-IC from the CBA using tweezers. (Fig. S-1-6) With Iron Wire: (1) Using desoldering braid, remove the solder from all pins of the flat pack-IC. When you use solder flux which is applied to all pins of the flat pack-IC, you can remove it easily. (Fig. S-1-3) (2) Affix the wire to a workbench or solid mounting point, as shown in Fig. S-1-5. (3) While heating the pins using a fine tip soldering iron or hot air blower, pull up the wire as the solder melts so as to lift the IC leads from the CBA contact pads as shown in Fig. S-1-5. (4) Bottom of the flat pack-IC is fixed with glue to the CBA; when removing entire flat pack-IC, first apply
Tweezers

Flat Pack-IC

Fig. S-1-6

3-2

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