Symmetricom 5071A, Operating And Programming Manual

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Appendix A Performance Tests
5071A Complete Performance Tests
Operating and Programming Manual 155
11 The frequency difference between the unit under test and the reference is given
by the following equation:
f/F = t/T
Where,
f/F is the desired frequency difference, and Dt is the phase change (in seconds)
over the measurement time, T.
The Figure A-8 shows a typical plot using the strip chart recorder.
Figure A-8. Error Measurement
In the example, the frequency difference, ( f)/F, is computed as follows:
f/F = t/T
= (7 minor divisions 2 10
-9
seconds/minor divisions)
= 14 10
-9
seconds
T = 8 hours or 2.88 10
4
seconds
f/F = t/T = 14 10
-9
/2.88 10
4
= 4.9 10
-13
or 4.9 parts in 10
13