HP 8647A Operation And Service Manual page 115

5b
Troubleshooting Information
Introduction
This chapter is intended to be used in conjunction with the
information in chapters 5a, 5c, and with your own troubleshooting
style. The troubleshooting reference information should contain the
details needed
as
you follow your troubleshooting process.
This chapter contains the following troubleshooting reference
information.
Troubleshooting Checklist
Use the troubleshooting checklist
as
a reminder of things to check.
w
AC Mains (Line) Fuse Removal
Use these instructions to replace the AC mains fuse.
w
Modulation Test Points and Power Supply LEDs Diagram
Use the diagram to check for the proper modulation reading and for
a quick visual check that the power supply voltages are present.
w
Power Supply Distribution Diagram
Use the diagram to identify the correct power supply voltage
distribution.
Instrument Block Diagram
The block diagram contains pin and connector designations as well
as input/output specifications.
See Chapter 5a, "Theory of Operation," for the block diagram
description.
Warning
The opening of covers or removal of parts is likely to expose
dangerous voltages. Disconnect the instrument from all voltage
sources while it is being opened.
The power cord is connected to internal capacitors that may
remain live for 5 seconds after disconnecting the plug from its
power supply.
Troubleshooting Information 5b-1