Motorola ASTRO XTSTM 4000, Detailed Service Manual

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6871620L01-C May 28, 2008
Troubleshooting Procedures: Handling Precautions 4-1
Chapter 4 Troubleshooting Procedures
The purpose of this chapter is to aid in troubleshooting problems with the ASTRO XTS 4000 radio. It
is intended to be detailed enough to localize the malfunctioning circuit and isolate the defective
component. It also contains a listing of service tools recommended for PC board repair at the
component level.
4.1 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.
1. Eliminate static generators (plastics, Styrofoam, etc.) in the work area.
2. Remove nylon or double-knit polyester jackets, roll up long sleeves, and remove or tie back
loose-hanging neckties.
3. Store and transport all static-sensitive devices in ESD-protective containers.
4. Disconnect all power from the unit before ESD-sensitive components are removed or inserted
unless otherwise noted.
5. Use a static-safeguarded workstation, which can be accomplished through the use of an
anti-static kit. This kit includes a wrist strap, two GROUND cords, a static-control table mat
and a static-control floor mat.
Most of the ICs are static sensitive devices. Do not attempt to
disassemble the radio or troubleshoot a board without first
referring to the following Handling Precautions section.
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