6-1
6.1
Introduction
The information in this section explains how to disassemble
the Model 6517A. Also discussed are handling and cleaning
considerations as well as the procedure to change the main
CPU firmware in the event of an upgrade.
WARNING
The information in this section is
intended only for qualified service per-
sonnel. Some of these procedures may
expose you to hazardous conditions. Do
not attempt these procedures unless you
are qualified to do so.
This section is organized as follows:
6.2
Handling and cleaning precautions:
Covers general
precautions to take when troubleshooting inside the
unit, and cleaning procedures when replacing parts.
6.3
Static-sensitive devices:
Explains handling proce-
dures for static-sensitive devices.
6.4
Case cover removal:
Explains how to remove the case
cover.
6.5
PC board removal:
Provides the procedures for
removing the digital board, A/D converter board, and
the analog board.
6.6
Front panel disassembly:
Explains how to remove
the display board.
6.7
Main CPU firmware replacement:
Provides the pro-
cedure to change firmware.
6.8
Instrument re-assembly:
Provides some general
guidelines to follow when re-assembling the Model
6517A.
6.9
Assembly drawings:
Provides mechanical drawings
to assist in the disassembly and re-assembly of the
Model 6517A.
6.2
Handling and cleaning precautions
When servicing the instrument, care should be taken not to
indiscriminately touch PC board traces to avoid contaminat-
ing them with body oils or other foreign matter. Analog
board areas covered by the shield have high-impedance
devices or sensitive circuitry where contamination could
cause degraded performance.
6.2.1 PC board handling
Observe the following precautions when handling PC
boards:
• Wear clean cotton gloves.
• Handle PC boards only by the edges and shields.
• Do not touch any board traces or components not asso-
ciated with the repair.
• Do not touch areas adjacent to electrical contacts.
• Use dry nitrogen gas to clean dust off PC boards.