Agilent Technologies E4406A Changing the View, •Limit Test - Turns off the limit test function

Making Measurements

Making the Adjacent Channel Power (ACP) Measurement

Res BW - This key is always grayed out. However, it allows you to see the resolution bandwidth that is derived from the combination of sweep time, data points, and FFT segments.

Num FFT Seg - The automatic mode selects the optimum number of FFT segments to measure the offset, while making the fastest possible measurement.

Relative Atten - Allows you to set a relative amount of attenuation for the measurements made at your offsets. The amount of attenuation is always specified relative to the attenuation that is required to measure the carrier channel. Since the offset channel power is lower than the carrier channel power, less attenuation is required to measure the offset channel and you get wider dynamic range for the measurement.

•Meas Type - Allows you to access the menu to select one of the measurement reference types.

—Total Pwr Ref - Select this to set the total carrier power to the measurement reference level and the measured data is shown in dBc and dBm.

—PSD Ref - Select this to set the mean power spectral density of the carrier to the measurement reference level and the measured data is shown in dB and dBm/Hz.

•Fast ACP - Allows you to increase the speed of the measurement. A time domain computation method is used rather than an FFT transformation. When this faster measurement method is selected, repeatability is slightly reduced.

•Spectrum Trace - Turns off the spectrum trace data calculations. This is only applicable when using the Spectrum View. It speeds up the display of the other measured data values by not calculating the spectrum trace.

•Limit Test - Turns off the limit test function.

Changing the View

The View/Trace key accesses the menu to select either Bar Graph or Spectrum for the measurement result, depending on the Sweep Type setting.

•Bar Graph - In the factory default condition 5 of the total integration power levels, centered at the carrier frequency and±750.0 kHz and

±1.98 MHz offset frequencies, are shown in the figure for the

“Results” section. The corresponding measured data is shown in the text window. Depending on the Meas Type selection, one of the two following displays is obtained:

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