Symmetricom 5071A, Assembly And Service Manual

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1. Performance Tests – Verifying Specifications
5071A Complete Performance Tests
14
g) When at least one sweep has completed, verify that there are no
spurious signals on or above the
−
80 dBc display line. Use the
knob in the marker area to move the offset marker to any spurious
signal that you want to measure or record. The marker shows the
offset frequency and level in dBc from the output signal at 5 or 10
MHz.
h) Verify that one of the following conditions is true:
No spurious signals are on or above the
−
80 dBc display line
between 4 MHz and 6 MHz for the 5 MHz output, or
No spurious signals are on or above the
−
80 dBc display line
between 9 MHz and 11 MHz for the 10 MHz output.
4 On the 5071A, set output ports 1 and 2 to 5 MHz using the front
panel controls.
5 Repeat step 3.
6 Connect 5071A Port 2 to the 3585B Spectrum Analyzer and
repeat steps 2 through 5 to test Port 2.
7 Record the actual reading in the appropriate place in the
Performance Test Record.
C. Harmonic Distortion Check for the 1 MHz Output
Harmonics on the 1 MHz output signal must be more than 40 dBc below the
fundamental. To perform this check, a spectrum analyzer is tuned to the
fundamental frequency and an amplitude reference is established. The output
frequency spectrum is then examined to determine the fundamental-to-
sideband amplitude relationship at harmonic points of the fundamental.
Equipment
HP/Agilent 3585B Spectrum Analyzer
Setup
Figure 1-5. 1MHz Output Harmonic Distortion Test Setup