Safe Handling Of Cmos And Ldmos; General Repair Procedures And Techniques - Motorola CDM Series Detailed Service Manual

Section 1: 2-2
2.2.2 Cleaning Internal Circuit Boards and Components
The only factory-recommended liquid for cleaning the printed circuit boards and their components is
isopropyl alcohol (100% by volume). Apply Isopropyl alcohol with a stiff, non-metallic, short-bristled
brush to dislodge embedded or caked materials located in hard-to-reach areas. The brush stroke
should direct the dislodged material out and away from the inside of the radio. Make sure that
controls or tunable components are not soaked with alcohol. Do not use high-pressure air to hasten
the drying process since this could cause the liquid to collect in unwanted places. Upon completion
of the cleaning process, use a soft, absorbent, lintless cloth to dry the area. Do not brush or apply
any isopropyl alcohol to the frame, front cover, or back cover.
NOTE Always use a fresh supply of alcohol and a clean container to prevent contamination by
dissolved material (from previous usage).
3.0

Safe Handling of CMOS and LDMOS

Complementary metal-oxide semiconductor (CMOS) devices are used in this family of radios. CMOS
characteristics make them susceptible to damage by electrostatic or high voltage charges. Damage
can be latent, resulting in failures occurring weeks or months later. Therefore, take special
precautions to prevent device damage during disassembly, troubleshooting, and repair.
CAUTION DO NOT attempt to disassemble the radio without first referring to the disassembly and
reassembly sections in the Basic Service Manual (Motorola Publication part number
6881091C62 [CDM Series models] or 6881092C71 [PRO Series models]).
Handling precautions are mandatory for CMOS circuits and are especially important in low humidity
conditions.
4.0

General Repair Procedures and Techniques

NOTE Environmentally Preferred Products (EPP) (refer to the marking on the printed circuit
boards – examples shown below) were developed and assembled using environmentally
preferred components and solder assembly techniques to comply with the European
Union's Restriction of Hazardous Substances (ROHS) Directive 2002/95/EC and
Waste Electrical and Electronic Equipment (WEEE) Directive 2002/96/EC. To
maintain product compliance and reliability, use only the Motorola specified parts in this
manual.
6881091C63-F
Safe Handling of CMOS and LDMOS