Symmetricom 5071A Assembly And Service Manual

2. Service
Top-Level Diagnostic Tree (Diagnostic Section 1)
43
VCXO Control Value
The frequency of the VCXO is continually adjusted by the frequency servo to
correct for noise and aging. The present state of the adjustment is provided
by the VCXO control value. This value has no discernible effect on instrument
operation as long as it remains within a 100% range. It is desirable to
schedule readjustment of the A19 frequency if the control value reaches 
90%. The adjustment procedure is provided at 3.9.1.7 and 3.9.1.8.
1.0.8.2 Conclusion of Diagnostic Procedure
If the results of the profiling procedure do not suggest CBT replacement, the
instrument can be returned to service. If repairs have been made, full
performance testing or operational verification must be performed as
described in chapter 1.
If a 5071A has been successfully tested as described above and fails to meet
specifications, you may need to return the instrument to the nearest qualified
repair facility. Contact Symmetricom for further assistance.

Symmetricom 5071A Specifications

General

Brand	Symmetricom
Model	5071A
Category	Measuring Instruments
Language	English