Quick Start: Learning How to Make Measurements

Learning to Make Transmission Measurements

Measuring Out-of-Band Rejection.

1.Press MARKER 1 . The marker appears where you placed it during the bandwidth measurement.

2.Press MKR ZERO Marker Search SEARCH: MIN .

The marker automatically searches for the minimum point on the trace. The frequency and amplitude of this point, relative to the delta symbol in the center of the filter passband, appear in the upper-right corner of the display. This value is the difference between the maximum power in the passband and the power in the rejection band, that is, one of the peaks in the rejection band.

Figure 2-6 Example Measurement of Out-of-Band Rejection

NOTE You can use the marker search mode to search the trace for the maximum point or for any target value. The target value can be an absolute level (for example, −3 dBm) or a level relative to the location of the small delta symbol (for example: −3 dB from the center of the passband).

3.If your measurement needs some noise reduction, you can reduce the IF bandwidth or add averaging.

To reduce the IF bandwidth, press Avg IF BW [ ]

.

To add averaging, press Avg , then toggle AVERAGING on OFF to ON.

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Chapter 2

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Agilent Technologies 8753ET, ES quick start Measuring Out-of-Band Rejection, Example Measurement of Out-of-Band Rejection