Agilent Technologies 8753ES Option 011 Service Manual page 263

Phase Lock Diagnostic Routines
Perform the following steps to determine at what frequencies and bands the phase lock
problem occurs.
1. Press
Preset System
switch off the automatic phase-locked loop. Normally, when the phase-locked loop
detects lock problems, it automatically aborts the sweep and attempts to recalibrate the
pretune cycle. Switching off PLL AUTO defeats this routine.
2. Press
PLL DIAG ON
this mode, the phase lock cycle and subsweep number are displayed on the analyzer
display. (See "Service Modes Menu" on page 10-16
3. Press
PLL PAUSE
is trying to tune when lock is lost.
Refer to "Source Theory Overview" on page 12-14
band related problems. Then use the procedures in this chapter to check source functions
at specific frequencies.
Chapter 7
SERVICE MENU
to switch on the phase-locked loop diagnostic service mode. In
to pause the phase lock sequence and determine where the source
Source Group Troubleshooting Appendix
SERVICE MODES
for more information.)
for additional information regarding
Source Troubleshooting
to
PLL AUTO OFF
7-31