User`s guide

Table Of Contents
Reference Graphs and Tables
16
Agilent E5505A User’s Guide 365
Increase in Measured Noise as Ref Source Approaches DUT Noise
The graph shown in Figure 291 demonstrates that as the noise level of the
reference source approaches the noise level of the DUT, the level measured by
the software (which is the sum of all sources affecting the test system) is
increased above the actual noise level of the DUT.
Figure 291 Reference source and DUT noise levels
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0.5
1.0
1.5
2.0
2.5
3.0
E5505a_inc_meas_noise
26 Feb 04 rev 1
Amount expected DUT noise exceeds reference noise (dB)
Increase in measured noise due
to reference noise (dB)