Toshiba TLP-450U, Service Manual

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2-1
SECTION 2
SER
VICING DIA
GRAMS
SECTION 2
SERVICING DIAGRAMS
1. PART CONFIGURATION AND THEIR SYMBOLS
1-1-4. Removal (Transistors, Diodes, etc.):
1. Melt the solder of one lead.
Fig. 2-1-4
2. Lift the side of that lead upward.
Fig. 2-1-5
3. Simultaneously heat solder the two remaining leads
and lift part to remove.
Fig. 2-1-6
1-1-5. Preheating (Except for semiconductors):
Immediately before installing new resistors or capacitors,
use a blower type hair dryer and preheat the part for about
two min. at approximately 150°C.
1-1-6. Replacement:
1. Presolder the contact points of the circuit pattern.
Fig. 2-1-7
2. Press the part downward with tweezers and apply the
soldering pencil as indicated in the figure.
Fig. 2-1-8
1. Fine tipped, well insulated soldering “pencil”, about
30 Watts.
2. Tweezers.
3. Blower type hair dryer.
1-1-2. Soldering Cautions:
1. Do not apply heat for more than 3s.
2. Avoid using a rubbing stroke when soldering.
3. Discard removed chips; do no reuse them.
4. Supplementary cementing is not required.
5. Use care not to scratch or otherwise damage the chips.
1-1-3. Removal (Resistors, Capacitors, etc.):
1. Melt the solder at one side.
Fig. 2-1-1
2. Grasp the part with tweezers and melt the solder at the
other side.
Fig. 2-1-2
3. Remove the part with a twisting motion.
Fig. 2-1-3
1-1. Replacing Subminiature "CHIP" Parts
1-1-1. Required Tools:
TWEEZERS
TWEEZERS
TWEEZERS