DOWNLOAD Panasonic KX-NS500UC (serv.man2) Service Manual ↓ Size: 12.71 MB | Pages: 127 in PDF or view online for FREE

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1. Loosen the 1 Screws(A), Remove the Fan Cover.
2. Remove the DC Motor.
3. Remove the 1connector  from the Mother Board.

4. Loosen the 2 Screws(A) and 2 Screws(E), Remove the Capacitor 

Cover.

5. Loosen the 2 Screws(E), Remove the Connect Plate.
6. Loosen the 7 Screws(E), Remove the Power Supply Board.
7. Remove the 1connector(AC Inlet Connect)  from the Power Sup-

ply Board.

8. Remove the 1connector  from the Mother Board.
9. Remove the Power Supply Board and Relay Board.
10. Remove the Relay Board from the Power Supply Board.

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Even if you do not have the special tools (for example, a spot heater) to remove the Flat IC, with some solder (large amount), a sol-
dering iron and a cutter knife, you can easily remove the ICs that have more than 100 pins.

• PbF (: Pb free) Solder
• Soldering Iron

Tip Temperature of 700

F ± 20F (370C ± 10C)

Note: We recommend a 30 to 40 Watt soldering iron. An
expert may be able to use a 60 to 80 Watt iron where some-
one with less experience could overheat and damage the
PCB foil.

• Flux

Recommended Flux: Specific Gravity 

 0.82.

Type 

 RMA (lower residue, non-cleaning type)

Note: See About Lead Free Solder (PbF: Pb free) (P.5).

1. Put plenty of solder on the IC pins so that the pins can be

completely covered.
Note:

If the IC pins are not soldered enough, you may give
pressure to the P.C. board when cutting the pins with
a cutter.

2. Make a few cuts into the joint (between the IC and its

pins) first and then cut off the pins thoroughly.

3. While the solder melts, remove it together with the IC

pins.

When you attach a new IC to the board, remove all solder
left on the land with some tools like a soldering wire. If some
solder is left at the joint on the board, the new IC will not be
attached properly.

1. Tack the flat pack IC to the PCB by temporarily soldering

two diagonally opposite pins in the correct positions on
the PCB.

Be certain each pin is located over the correct pad on the PCB.

2. Apply flux to all of the pins on the IC.

3. Being careful to not unsolder the tack points, slide the sol-

dering iron along the tips of the pins while feeding enough
solder to the tip so that it flows under the pins as they are
heated.

1. Add a small amount of solder to the bridged pins.
2. With a hot iron, use a sweeping motion along the flat part

of the pin to draw the solder from between the adjacent
pads.

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• PbF (: Pb free) Solder
• Soldering Iron

Tip Temperature of 700 

F ± 20 F (370 C ± 10 C)

Note:
We recommend a 30 to 40 Watt soldering iron. An expert may be able to use a 60 to 80 Watt iron where someone with less 
experience could overheat and damage the PCB foil.

• Hot Air Desoldering Tool

Temperature: 608 

F ± 68 F (320 C ± 20 C)

• To replace the IC efficiently, choose the right sized nozzle of the hot air desoldering tool that matches the IC package.
• Be careful about the temperature of the hot air desoldering tool not to damage the PCB and/or IC.

1. Heat the IC with a hot air desoldering tool through the

P.C.Board.

2. Pick up the IC with tweezers, etc. when the solder is

melted completely.
Note:

• Be careful not to touch the peripheral parts with twee-

zers, etc. They are unstable. 

3. After removing the IC, clean the P.C.Board of residual sol-

der.

1. Place the solder a little on the land where the radiation

GND pad on IC bottom is to be attached.

2. Place the solder a little on the land where IC pins are to

be attached, then place the IC.
Note:

• When placing the IC, the positioning should be done very

carefully.

3. Heat the IC with a hot air desoldering tool through the

P.C.Board until the solder on IC bottom is melted.
Note:

• Be sure to place it precisely, controlling the air volume of

the hot air desoldering tool.

4. After soldering, confirm there are no short and open cir-

cuits with visual inspection.

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When a Solder Bridge is found after soldering the bottom of the IC, remove it with a soldering iron.