Symmetricom 5071A, Assembly And Service Manual

Page: 34 / 202

1. Performance Tests – Verifying Specifications
5071A Complete Performance Tests
18
Test 2 — Frequency Accuracy
The following accuracy check measures the changing phase relationship
between the 5071A 10 MHz output and another primary frequency standard
(5071A Primary Frequency Standard or better). An HP/Agilent K34-59991A
Linear Phase Comparator is used to measure the phase between the 5071A
under test and the reference standard.
NOTE
In this test, the reference standard must be of known accuracy. The
measurement time must be of sufficient length so the accuracy of
the measurement is not impaired by the stability of either the
reference standard or the unit under test. If the reference standard is
a 5071A with the High-Performance CBT, the accuracy
measurement must be made for 24 hours if the unit under test is a
Long-Life (Standard) CBT. The test can be made in 2 1/2 hours if
the unit under test has the High-Performance CBT.
Equipment
HP/Agilent K34-59991A Linear Phase Comparator
Strip Chart Recorder
Setup
Figure 1-7. Frequency Accuracy Test Setup