Motorola ASTRO W5, Руководство по обслуживанию

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September 26, 2003 6881096C77-O
2-2 Basic Maintenance: Handling Precautions
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.
• Use a static-safeguarded workstation through the use of an anti-static kit (Motorola part number
01-80386A82). This kit includes a wrist strap, two ground cords, a static-control table mat and a
static-control floor mat.
NOTE: Be sure that the table and floor mats are properly grounded.
When these items are not readily available, observing the following techniques will minimize the
chance of damage:
- If a static-sensitive device is to be temporarily set down, use a conductive surface for place-
ment of the device.
- Make skin contact with a conductive work surface first and maintain this contact when the
device is set down or picked up.
- Always wear a conductive wrist strap when servicing this equipment. The Motorola part
number for a replacement wrist strap that connects to the table mat is 42-80385A59
Components used in this equipment can be damaged by
accumulated static charge. Avoid unnecessary handling.
When handling devices, use a group strap, conductive
benches, and floor mats to ensure that a static charge does
not develop on component terminals. Always pick up
components by the body when possible, avoiding the
electrical terminals. Exposed connections should be shorted
together via conductive foam when not in use.
Use grounded equipment when performing tests. DO NOT
connect components to or disconnect components from test
equipment while power is applied.
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