Making Basic Measurements Using Spectrum Analyzer Made

Identifying Distortion Products Using the RF Attenuator and Traces

Example: Using a signal from a signal generator, determine whether the harmonic distortion products are generated by the spectrum analyzer.

1.Connect a signal generator to the spectrum analyzer’s INPUT 75 0. Set the signal generator frequency to 200 MHz and the amplitude to 0 dBm.

Set the center frequency of the spectrum analyzer to 400 MHz and the span to 500 MHz: press [FREQUENCY), 400 IIVIHz), ISPAN) 500 (MHz). The signal shown in Figure 4-20 produces harmonic distortion products in the spectrum analyzer’s input mixer.

2.Change the span to 200 MHz: press ISPAN), 200 (MHz).

3.Change the attenuation to 0 dB: press c-1, ATTEN AUTO MAN , 0 (dBmV).

4.To determine whether the harmonic distortion products are generated by the spectrum analyzer, first save the screen data in trace B.

Press Cm), TRACE A 3 C (until trace B is underlined), then CLEAR WRITE B Allow the trace to update (two sweeps) and press

VIEW B , [PEAK SEARCH), MARKER A The spectrum analyzer display shows the stored data in trace B and the measured data in trace A.

5. Next, increase the RF attenuation by 10 dB: press (j-1, ATTEN AUTO MAN , and the step-up key (m) once. (See Figure 4-21.)

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