Symmetricom 5071A, Сборка и сервисное обслуживание

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1. Performance Tests – Verifying Specifications
5071A Complete Performance Tests
19
Specifications
Long-Life (Standard):
±
1x10
−
12
High-Performance:
±
2x10
−
13
NOTE
The accuracy of the 5071A is better than 2x10
-13
(High-Performance) o
1x10
-12
(Long-Life). Be sure the accuracy of the reference standard is
known with sufficient precision to make this measurement accurately.
Procedure
1 The 5071A must be on for at least 30 minutes and the green
continuous operation LED must be on.
2 Connect the HP/Agilent K34-59991A Phase Comparator OUTPUT
terminals to the strip chart recorder as shown in Figure 1-7. Set
the recorder for 1V full scale and 1 inch/hour. Turn on the
recorder.
3 Turn on the K34-59991A power.
4 Connect the 10 MHz reference to INPUT A and the 5071A (unit
under test) 10 MHz to INPUT B as shown in Figure 1-7.
5 Set K34-59991A “ZERO-OPER-FULL” front panel mounted toggle
switch to “ZERO.” Adjust the “ZERO SCALE” control for a zero
reading on the meter. Then adjust the recorder for a zero
indication.
6 Set K34-59991A switch to “FULL” and adjust “FULL SCALE”
control for a full scale reading on the recorder.
7 Check both “ZERO” and “FULL SCALE” settings on the recorder
and readjust if necessary.
8 Set K34-59991A switch to “OPER” for normal operation.
9 The recorder now provides a continuous record of the phase
difference between the reference standard and the 5071A unit
under test. When its output reaches full scale (360 degrees), the
K34-59991A will automatically reset to 0 (0 degrees).
10 With the recorder set as described, the phase record is 100 ns full
scale (with 10 MHz inputs). The figure below shows an example of
a frequency difference measurement under these conditions.
11 The frequency difference between the unit under test and the
reference is given by the following equation:
Δ
f/F =
Δ
t/T
Where:
Δ
f/F is the desired frequency difference, and
Δ
t is the
phase change (in seconds) over the measurement time, T.
The Figure 1-8 shows a typical plot using the strip chart recorder.