Identifying Distortion Products Using The Rf Attenuator And Traces; Distortion From The Analyzer; Harmonic Distortion - HP 8590 E-Series User Manual

Identifying Distortion Products Using the RF Attenuator and
Traces

Distortion from the Analyzer

High-level input signals may cause spectrum analyzer distortion products that could mask the
real distortion measured on the input signal. Using trace B and the RF attenuator, you can
determine which signals, if any, are internally generated distortion products.
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 INPUT 500. 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 (-1, 400 m, (SPAN) 500 m. The signal shown in Figure 3-21 produces
harmonic distortion products in the spectrum analyzer input mixer.
2. Change the span to 200 MHz: press (SPAN), 200 INIHz).
4. To determine whether the harmonic distortion products are generated by the spectrum
analyzer, first save the screen data in trace B.
Press (ml, TRACE A B C (until trace B is underlined), then CLEAR WRITE B . Allow the
trace to update (two sweeps) and press VIEW B
analyzer display shows the stored data in trace B and the measured data in trace A.
step-up key (m) once. See Figure 3-22.
PEAK
LOG
10
WA SE
S C F(
Figure 3-2 1. Harmonic Distortion
MARKER A . The spectrum