Keysight U8903B User Manual page 202

4 Audio Analyzer Measurement Functions
Table 4-11 Analog/Digital/Bluetooth Analyzer > Functions > SINAD menu description (continued)
Menu Description
Press the Freq Lock softkey to select the searching method for the fundamental frequency.
– Auto
Selecting Auto will allow the U8903B to search for the fundamental frequency automatically.
– Gen Lock
Selecting Gen Lock will allow the U8903B to search for the fundamental frequency based on the generator frequency
Freq Lock
value of the respective generator channel. You can select the generator channel by setting the Src Channel in the Meas.
Config. menu page. This Gen Lock method is only useful if you use the internal audio generator.
– Custom
If you have a known input signal, you can define the fundamental frequency value by setting the searching method to
Custom and setting the frequency value in Fund Freq.
Press the Fund Freq softkey to set the fundamental frequency value. This setting is only available when Freq Lock is set to
Fund Freq
Custom.
202 Keysight U8903B User's Guide