Specifications

Chapter 13 117
Stimulus Response Measurements (ESA Options 1DN and 1DQ)
Measuring Stop Band Attenuation Using Log Sweep (ESA-E Series)
Stimulus Response Measurements
(ESA Options 1DN and 1DQ)
Step 7. Put the sweep time into stimulus response auto coupled mode:
Press
Sweep, Swp Coupling (SR).
Adjust the reference level if necessary to place the signal on screen.
Step 8. Connect the cable (but not the DUT) from the tracking generator output
to the analyzer input. Store the frequency response into trace 3 and
normalize:
Press
View/Trace, More, Normalize, Store Ref (1→3), Normalize (On).
Step 9. Reconnect the DUT to the analyzer. Note that the units of the reference
level have changed to dB, indicating that this is now a relative
measurement.
Step 10. To change the normalized reference position:
Press
View/Trace, More, Normalize, Norm Ref Posn, 9, Enter.
Step 11. Place the reference marker at the specified cutoff frequency:
Press
Marker, Delta Pair (Ref), 10, MHz.
Step 12. Place the second marker at 20 MHz:
Press
Delta Pair (Delta), 20, MHz.
In this example, the attenuation over this frequency range is
63.32 dB/octave (one octave above the cutoff frequency).
Step 13. Use the front-panel knob to place the marker at the highest peak in the
stop band to determine the minimum stop band attenuation. In this
example, the peak occurs at 708.76 MHz. The attenuation is 54.92 dB.
Figure 13-6 Minimum Stop Band Attenuation