Motorola GM140, Базовое руководство по обслуживанию

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Repair Procedures and Techniques — General 3-3
4.0 Repair Procedures and Techniques — General
Parts Replacement and Substitution
When damaged parts are replaced, identical parts should be used. If the identical replacement part
is not locally available, check the parts list for the proper Motorola part number and order the part
from the nearest Motorola Communications parts center listed in the “Piece Parts” section of this
manual.
Rigid Circuit Boards
This 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 printed-through holes may interconnect multiple layers of the printed circuit. Therefore, exercise
care to avoid pulling the plated circuit out of the hole.
When soldering near the 20-pin and 40-pin connectors:
Avoid accidentally getting solder in the connector.
Be careful not to form solder bridges between the connector pins.
Examine your work closely for shorts due to solder bridges.
5.0 Disassembling and Reassembling the Radio — General
Since these radios may be disassembled and reassembled with the use of only four (board to
casting) screws, it is important to pay particular attention to the snaps and tabs, and how parts align
with each other.
The following tools are required for disassembling the radio:
Small flat blade screwdriver
Dismantling Tool (Motorola Part No. 6686119B01)
TORX™ T20 screwdriver
If a unit requires more complete testing or service than is customarily performed at the basic level,
send this unit to a Motorola Authorized Service Center. (See Chapter 1 for a list of authorized
service centers.)
The following disassembly procedures should be performed only if necessary: