Service Manual

MM-E 2072-09333-00
3-1
Chapter 3
MAINTENANCE
3-1. SCOPE
This Chapter provides maintenance instructions for Micom-Z.
The information presented in this Chapter covers testing, troubleshooting procedures, and repair
instructions. Use Appendix B to identify components and find other data needed for troubleshooting
and repair.
3-2. HANDLING PRECAUTIONS DURING MAINTENANCE
Equipment maintenance is performed in accordance with standard practice. During equipment
maintenance, observe the following precautions:
a. To preserve equipment reliability, the equipment should be serviced only in a protected, clean
environment.
b. Electronic components, in particular CMOS and RF devices, are susceptible to damage by
electrostatic discharge (ESD). Electrostatic charge is created by friction between different
bodies, including the human body, especially under dry conditions. 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. To prevent
damage, use the following 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.
• Disconnect all power from the unit before starting repair activities.
• Use a static safeguarded workstation, which can be accomplished through the use of an anti-
static kit, which typically includes a wrist strap, two ground cords, a static-control table mat,
and a static-control floor mat.
When these items are not readily available, observing the following techniques will
minimize chance of damage:
 If a static-sensitive device is to be temporarily set down, use a conductive surface for
placement 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.
c. Keep any module (good or defective) in the original packaging, even when the module is placed
on the workbench.
d. Handle modules carefully; do not drop modules, and avoid piling them up, because the exposed
components may be damaged by physical stress and shock. Always use the original packaging
of the module and do not use alternative packaging, unless the original one is damaged or lost.
The original packaging is designed to absorb mechanical shocks and to protect the equipment
against electrostatic discharge.
e. Hold a module by its sides, and avoid touching its connectors or electronic components installed
on the module. This practice will prevent mechanical damage, oily deposits on contacts and
damage due to electrostatic discharge.