Motorola CDM1250, Basic Service Manual

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Maintenance 2-3
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:
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Avoid accidentally getting solder in the connector.
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Be careful not to form solder bridges between the connector pins.
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Examine your work closely for shorts due to solder bridges.
2.5 Disassembling and Reassembling the Radio — General
Since these radios may be disassembled and reassembled with the use of only six (board to casting)
screws (nine for LowBand), 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:
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Small flat blade screwdriver
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TORX™ T20 screwdriver
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Dismantling Tool
If a unit requires more complete testing or service than is customarily performed at the basic level,
send the unit to a Motorola Authorized Service Center. (See Chapter 1, Introduction for a list of
regional service centers.)
The following disassembly procedures should be performed only if necessary.
2.6 Radio Disassembly — Detailed
The procedure to remove and replace a control head is similar for all models of radio. A typical
procedure is therefore shown followed by specific disassembly procedures for the different control
heads.
2.6.1 Control Head Removal
1. Insert the dismantling tool in the groove between the control head and the radio assembly as
shown in Figure 2-1, on page 2-19.
2. Press on the dismantling tool until the snap connectors on the side of the control head release
from the radio assembly.