Motorola EP350 Basic Service Manual page 69

Maintenance – EP350 (Full Keypad Model): Repair Procedures and Techniques – General
Shields
Removing and replacing shields is recommended to be done with the Air Blower,
BOSCH GHG 603 or equivalent.
• To remove the shield:
1. Place the circuit board in the circuit board holder.
2. Add solder paste flux around the base of the shield.
3. Position the heat-focus head onto the shield.
4. Turn on the heater and wait until the shield lifts off the circuit board.
5. Once the shield is off, turn off the heat, and grab the part with a pair of tweezers.
6. Remove the circuit board from the circuit board holder.
• To replace the shield:
1. Add solder to the shield if necessary, using a micro-tipped soldering iron.
2. Next, rub the soldering iron tip along the edge of the shield to smooth out any excess
solder. Use solder wick and a soldering iron to remove excess solder from the solder
pads on the circuit board.
3. Place the circuit board back in the circuit board holder.
4. Place the shield on the circuit board using a pair of tweezers.
5. Position the heat-focus head over the shield.
6. Turn on the heater and wait for the solder to reflow.
7. Once complete, turn off the heat, raise the heat-focus head and wait approximately one
minute for the part to cool.
8. Remove the circuit board and inspect the repair. No cleaning should be necessary.
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