HP 8920A Application Handbook page 201

Test Set Options Required
Additional Equipment
Required
NOTE:
Spectrum Analyzer/Tracking Generator (option 102)
Whip Antenna
When two signals F1 and F2 are present in a system, they can mix with the
second harmonics generated 2F1 and 2F2 and create higher order inter-
modulation distortion products. Because these distortion products are usually
located close to the original signals at 2F2 - F1 and 2F1 - F2, span should be
reduced to as narrow as possible while still allowing the distortion products to
be displayed.
Using the Spectrum Analyzer
201