Agilent Technologies 8753ES Option 011 Service Manual page 242

Source Troubleshooting
Phase Lock Error
6. The signal observed on the spectrum analyzer will appear jittery as in
not solid as in Figure 7-5
phase locked.
Figure 7-5 Phase Locked Output Compared to Open Loop Output in SRC Tune
Mode
7. Press to vary the power and check for corresponding level changes on the test
Power
instrument. (A power change of 20 dB will change the voltage observed on the
oscilloscope by a factor of ten.)
8. Note the results of the frequency and power changes:
• If the frequency and power output changes are correct, skip ahead to
Check" on page
• If the frequency changes are not correct, continue with
Analog Bus" on page
• If the power output changes are not correct, check analog bus node 3 by performing
the following steps:
a. Press
System
S PARAMETERS
b. Press
Marker
c. Press
Marker
7-10
(A). This is because in SRC TUNE mode the output is not
7-12.
7-11.
SERVICE MENU
ANALOG IN Aux Input
. The marker should read approximately 434 mU.
2 G/n
. The marker should read approximately 646 mU.
4 G/n
"YO Coil Drive Check with
ANALOG BUS ON
Format MORE
Figure 7-5 (B),
"A12 Reference
Meas
REAL 3 x1
Chapter 7
.