Motorola GP Series Detailed Service Manual page 23

General Repair Procedures and Techniques
Any rework or repair on Environmentally Preferred Products must be done using the appropriate
lead-free solder wire and lead-free solder paste as stated in the following table:
Motorola
Part Number
1088929Y01 95.5Sn/3.8Ag/0.7Cu
1088929Y02 95.5Sn/3.8Ag/0.7Cu
1088929Y03 95.5Sn/3.8Ag/0.7Cu
Motorola Part Manufacturer Part
Number
10-856-74C03
Parts Replacement and Substitution
When damaged parts are replaced, identical parts should be used. If the identical replacement
component is not locally available, check the parts list for the proper Motorola part number and
order the component from the nearest Motorola Communications parts center listed in the "Piece
Parts" section of this manual.
Rigid Circuit Boards
The family of radios uses bonded, multi-layer, printed circuit boards. Since the inner layers are
not accessible, some special considerations are required when soldering and unsoldering
components. The through-plated holes may interconnect multiple layers of the printed circuit.
Therefore, care should be exercised to avoid pulling the plated circuit out of the hole.
When soldering near the 18-pin and 40-pin connectors:
• avoid accidentally getting solder in the connector.
• be careful not to form solder bridges between the connector pins
• closely examine your work for shorts due to solder bridges.
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 390 °C (735 °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:
Table 2-1 Lead Free Solder Wire Part Number List
Alloy Flux Type
RMA Version
RMA Version
RMA Version
Table 2-2 Lead Free Solder Paste Part Number List
Viscosity
Number
NC-SMQ230 900-1000KCPs
Brookfield (5rpm)
Flux Content Melting
by Weight Point
2.7-3.2% 217C
2.7-3.2% 217C
2.7-3.2% 217C
Type Composition & Percent Metal
Type 3 (95.5%Sn-3.8%Ag-0.7%Cu)
(-325/+500)
Supplier Part
Diameter
number
52171 0.015"
52170 0.010"
52173 0.032"
Temperature
89.3%
2-3
Weight
1lb spool
0.5lb spool
1lb spool
Liquid
217°C