Motorola GM338, Service Manual

Page: 23 / 556

General Repair Procedures and Techniques 2-3
Chip Components
Use either the RLN4062 Hot-Air Repair Station or the Motorola 0180381B45 Repair Station for chip
component replacement. When using the 0180381B45 Repair Station, select the TJ-65 mini-
thermojet hand piece. On either unit, adjust the temperature control to 370 °C (700 °F), and adjust
the airflow to a minimum setting. Airflow can vary due to component density.
•
To remove a chip component:
1. Use a hot-air hand piece and position the nozzle of the hand piece approximately 0.3 cm (1/
8") above the component to be removed.
2. Begin applying the hot air. Once the solder reflows, remove the component using a pair of
tweezers.
3. Using a solder wick and a soldering iron or a power desoldering station, remove the excess
solder from the pads.
•
To replace a chip component using a soldering iron:
1. Select the appropriate micro-tipped soldering iron and apply fresh solder to one of the solder
pads.
2. Using a pair of tweezers, position the new chip component in place while heating the fresh
solder.
3. Once solder wicks onto the new component, remove the heat from the solder.
4. Heat the remaining pad with the soldering iron and apply solder until it wicks to the compo-
nent. If necessary, touch up the first side. All solder joints should be smooth and shiny.
•
To replace a chip component using hot air:
1. Use the hot-air hand piece and reflow the solder on the solder pads to smooth it.
2. Apply a drop of solder paste flux to each pad.
3. Using a pair of tweezers, position the new component in place.
4. Position the hot-air hand piece approximately 0.3 cm (1/8” ) above the component and begin
applying heat.
5. Once the solder wicks to the component, remove the heat and inspect the repair. All joints
should be smooth and shiny.