Panasonic PT-47WX33G, Service Manual

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4. Service notes
NOTE
These components are affixed with glue. Be careful not to break or damage any foil under the
component or at the pins of the ICs when removing. Usually applying heat to the component for
a short time while twisting with tweezers will break the component loose.
Leadless chip component (surface mount)
Chip components must be replaced with identical chips due to critical foil track spacing. There
are no holes in the board to mount standard transistors or diodes. Some chips capacitor or
resistor board solder pads may have holes through the board,however the hole diameter limits
standard resistor replacement to 1/8 watt. Standard capacitor may also be limited for the same
reason. It is recommended that identical components be used.
Chip resistor have a three digit numerical resistance code, 1st and 2nd significant digits and a
multiplier. Example: 162 = 1600 or 1.6k resistor, 0 = 0 (jumper).
Chip capacitors generally do not have the value indicated on the capacitor. The color of the
component indicates the general range of the capacitance.
Chip transistors are identified by a two letter code. The first letter indicates the type and the
second letter, the grade of transistor.
Chip diodes have a two letter identification code as per the code chart and are a dual diode pack
with either common anode or common cathode. Check the parts list for correct diode number.
Component removal
1. Use solder wick to remove solder from component end caps or
terminal.
2. Without pulling up, carefully twist the component with tweezers to
break the adhesive.
3. Do not reuse removed leadless or chip components since they
are subject to stress fracture during removal.
Chip component installation
1. Put a small amount of solder on the board soldering pads.
2. Hold the chip component against the soldering pads with
tweezers or with a miniature alligator clip and apply heat to the
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