Source Check; Phase Lock Error Messages - Agilent Technologies 8719ET Service Manual

8719ET/20ET/22ET
8719ES/20ES/22ES
RF Network Analyzers

Source Check

Phase Lock Error Messages

The following list contains all phase lock error messages and their descriptions.
• NO IF FOUND: CHECK R INPUT LEVEL
The first IF was not detected during the pretune stage of phase lock.
• NO PHASE LOCK: CHECK R INPUT LEVEL
The first IF was detected at the pretune stage but phase lock could not be acquired
thereafter.
• PHASE LOCK LOST
Phase lock was acquired but then lost.
• PHASE LOCK CAL FAILED
An internal phase lock calibration routine is automatically executed at power-on, when
pretune values drift, or when phase lock problems are detected. A problem aborted a
calibration attempt.
• POSSIBLE FALSE LOCK
The analyzer is achieving phase lock but possibly on the wrong harmonic comb tooth.
• SWEEP TIME TOO FAST
The fractional-N and the digital IF circuits have lost synchronization.
The error messages listed above usually indicate a source failure or improper instrument
configuration.
For ES Models, Check the R Channel
As a preliminary step, ensure that all option jumper cables are properly connected. To
ensure that the R channel input is receiving at least −35 dBm power, perform the following
steps:
1. Perform steps 1 and 2 of
Make note of the DAC number that is displayed and then abort the procedure.
2. Press the following:
SERVICE MENU
System
SRC ADJUST MENU
3. Enter the DAC number determined from step 1 and press
4. Disconnect the front panel R CHANNEL jumper.
5. Zero and calibrate a power meter. Connect the power sensor to R CHANNEL OUT.
6. The power meter should read greater than
Service Guide
"Source Pretune Correction Constants (Test 43)" on page
SERVICE MODES
DACNUM HIGH BAND
−
35 dBm.
Start Troubleshooting Here
Source Check
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