Agilent Technologies E4406A manual In addition, the following parameters can be modified

Making Measurements

Making the Waveform (Time Domain) Measurement

In addition, the following parameters can be modified:

•Sweep Time - Allows you to specify the measurement acquisition time which is used as the length of the time capture record. The range is

1.0∝s and 100.0 s, depending upon the resolution bandwidth setting and the available internal memory size for acquisition points.

•Res BW - Allows you to set the measurement bandwidth. The range is 10 Hz to 7.5 MHz. A larger bandwidth results in a larger number of acquisition points and reduces the maximum value allowed for the sweep time.

•Advanced - Allows you to access the menu to change the following parameters. Changes from the default values may result in invalid data.

— Pre-ADC BPF - Allows you to toggle the pre-ADC bandpass filter function between On or Off. The default setting is Off. The pre-ADC bandpass filter is useful for rejecting nearby signals, so that sensitivity within the span range can be improved by increasing the ADC range gain.

— RBW Filter - Allows you toggle the resolution bandwidth filter selection between Flat and Gaussian. If set to Gaussian, the filter provides more even time-domain response, particularly for “bursts”. If set to Flat, the filter provides a flatter bandwidth but is less accurate for “pulse responses”. A flat top filter also requires less memory and allows longer data acquisition times. For most waveform applications, the Gaussian filter is recommended.

— ADC Range - Allows you to access the menu to select one of the ADC ranging functions:

❏Auto - Select this to cause the instrument to automatically adjust the signal range for optimal measurement results.

❏AutoPeak - Select this to cause the instrument to continuously seek the highest peak signal.

❏AutoPeakLock - Select this to cause the instrument to adjust the range for the highest peak signal it identifies, and retains the range settings determined by that peak signal, even when the peak signal is no longer present.

❏Manual - Allows you to access the selection menu: −6 dB, 0 dB, +6 dB, +12 dB, +18 dB, +24 dB, to set the ADC range level. Also note that manual ranging is best for CW signals.

—Data Packing - Allows you to select Auto (the default) or the Short (16 bit), Medium (24 bit) and Long (32 bit) methods of data packing. The short, medium, and long methods are not compatible with all settings and should not be used unless you are familiar with data packing methods. Auto is the preferred choice.

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