Keysight U8903B User Manual page 205

Table 4-12 Analog/Digital/Bluetooth Analyzer > Functions > THD Ratio menu description (continued)
Menu Description
Press the Format softkey to select the format of the returned measurement reading.
– Off
Selecting Off will return the measurement reading without any formatting (raw value).
– Delta
Format
Selecting Delta will return the measurement result by deducting the reference ratio from the measured ratio. The result
will be returned in unit ΔdB.
– Linear
Selecting Linear will return the measurement result by dividing the measured ratio by the reference ratio. The result is
returned in unit x.
This is only available for analog analyzer.
Set to 0dB
Press the Set to 0dB softkey to store the measured ratio as the reference ratio, and set the measurement reading format to
Delta.
Set result as ref. from Press the Set resul t as ref. from softkey to store the measurement result from the selected channel as the reference ratio.
Ref. Ratio Press the Ref. Ratio softkey to set the reference ratio value.
Press the Even Harmonic softkey to display the even harmonics order selection. Press the Enter key on the navigation
panel to select the desired even harmonics order, and press the Even Harmonic softkey again to confirm the selection.
– ALL
– 2
Even Harmonic
– 4
– 6
– 8
Press the Odd Harmonic softkey to display the odd harmonics order selection. Press the Enter key on the navigation panel
to select the desired odd harmonics order, and press the Odd Harmonic softkey again to confirm the selection.
– ALL
– 3
Odd Harmonic
– 5
– 7
– 9
This is only available for analog and Bluetooth analyzer.
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
Freq Lock
Selecting Gen Lock will allow the U8903B to search for the fundamental frequency based on the generator frequency
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.
Keysight U8903B User's Guide
Audio Analyzer Measurement Functions 4
205