Keysight FieldFox B Series User Manual page 635

AM/FM Metrics (SA Only and Option 355)
Interpreting AM/FM Metrics Error Messages
Test Tone Not Found - Corrected Example
The following response was corrected with these setting changes:
— Frequency set to narrower frequency span of 50 kHz
— Ideally the frequency span should show the modulation envelope down to
Response corrected, because:
— Narrowing the frequency span enables the modulation envelope's side
— FM algorithm identifies the side lobes
— The algorithm matches the modulation envelope to the mathematically
Figure 27-8 Test Tone Not Found - Corrected Example
Keysight N9938-90006 User's Guide
–60 dB below the RF power level
lobes to be identified
calculated FM modulation or distortion patterns
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