HP 85640A, Руководство по эксплуатации и обслуживанию

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Figure 3-9. F aster Sweep Times in Stimulus-Response A uto-Coupled Mode
9. Because this test is for bandpass lter rejection only , tune the spectrum analyzer so the
lter's roll-o takes up most of trace on the display . Set the start frequency to 1 MHz and
the stop frequency to 1 GHz, as shown in Figure 3-10 .
Figure 3-10. A djusting the Spectrum Analyzer for Measurement Requirements
10. Decrease resolution bandwidth to reduce the displayed average noise level. Press
4 BW 5
NNNNNNNNNNNNNNNNNNNN
RES BW (to select MAN), then press 4 + 5 on the spectrum analyzer . In Figure 3-11,
resolution bandwidth is set at 300 kHz.
11. Narrow video bandwidth to smooth the noise; press
NNNNNNNNNNNNNNNNNNNNNNNNNN
VIDEO BW (to select MAN), then press
4
+
5 on the spectrum analyzer . In Figure 3-11 , video bandwidth is set at 300 Hz.
3-12 Operation HP 85640A RF T racking Generator Operation and Service Manual