Motorola PM1200, Basic Service Manual

Page: 28 / 138

October 26, 2007 6880309U09-A
2-2 Basic Maintenance : Handling Precautions
2.2.2.1 Cleaning External Plastic Surfaces
The detergent-water solution should be applied sparingly with a stiff, non-metallic, short-bristled
brush to work all loose dirt away from the radio. A soft, absorbent, lint-free cloth or tissue should be
used to remove the solution and dry the radio. Make sure that no water remains entrapped near the
connectors, cracks, or crevices.
2.2.2.2 Cleaning Internal Circuit Boards and Components
Isopropyl alcohol may be applied 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. Be careful not to break off electrical components.
Alcohol is a high-wetting liquid and can carry contamination into unwanted places if an excessive
quantity is used. Make sure that controls or tunable components are not soaked with the liquid. Do
not use high-pressure air to hasten the drying process, since this could cause the liquid to puddle
and collect in unwanted places.
Upon completion of the cleaning process, use a soft, absorbent, lint-free cloth to dry the area. Do not
brush or apply any isopropyl alcohol to any plastic parts.
NOTE: Always use a fresh supply of alcohol and a clean container to prevent contamination by
dissolved material (from previous usage).
2.2.3 General Radio Care and Handling Precautions
• Avoid physical abuse: do not pound, drop, or throw the radio. Exposed parts, such as controls
and connectors, might be damaged.
• Operating the radio without an antenna cable attached may lead to radio failure and may void
the warranty.
2.2.4 RF Power Amplifier (RF PA) Heatsinking
Never transmit unless the printed-circuit board (PCB) DC and RF connector clips and internal screws
are installed in the chassis. Doing so can result in immediate failure of RF PA devices or greatly
reduced RF PA device life. It is possible to transmit with the chassis eliminator for short periods if
used properly.
2.3 Handling Precautions
Complementary metal-oxide semiconductor (CMOS) devices, and other high-technology devices,
are used in this family of radios. While the attributes of these devices are many, their characteristics
make them susceptible to damage by electrostatic discharge (ESD) or high-voltage charges.
Damage can be latent, resulting in failures occurring weeks or months later. Therefore, special
precautions must be taken to prevent device damage during disassembly, troubleshooting, and
repair. Handling precautions are mandatory for this radio, and are especially important in low-
humidity conditions. DO NOT attempt to disassemble the radio without observing the following
handling precautions:
• Eliminate static generators (plastics, styrofoam, etc.) in the work area.
• Remove nylon or double-knit polyester jackets, roll up long sleeves, and remove or tie back
loose-hanging neckties.
• Store and transport all static-sensitive devices in ESD-protective containers.
• Disconnect all power from the unit before ESD-sensitive components are removed or inserted
unless otherwise noted.