Spectrum (User Correction)

Menu Path: Input > User Correction

The Spectrum parameter controls whether the signal is inverted or not. If the IF output from the external downconverter is inverted with respect to the input, the VSA will reinvert the signal to obtain the correct spectrum.

Normal: Does not invert the signal.
Inverted: Inverts the signal.

If using an external downconverter, use this parameter to invert the frequency. This will ensure that the frequency marker will report the correct frequency for the dignal under overvation.

The Mirror Frequency control in the Frequency tab of the Meas Setup dialog box merely reflects the spectrum display about the current center frequency and does not preserve the correct absolute frequency of any aspect of the signal.