Keysight U8903B, User Manual

Page: 199 / 605

Audio Analyzer Measurement Functions 4
Keysight U8903B User’s Guide 199
Format
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).
– Logarithmic
Selecting Logarithmic will return the measurement result by using the following formula:
The result is returned in unit dBr.
– Linear
Selecting Linear will return the measurement result by dividing the measured level by the reference level. The result is
returned in unit x.
– Delta
Selecting Delta will return the meausrement result by deducting the reference level from the measured level. The result
is returned in unit
Δ
V. This is only available for the analog analyzer.
Set to 0dB
This is only available for analog analyzer.
Press the
Set to 0dB softkey to store the measured level as the reference level, and set the measurement reading format to
Logarithmic.
Set result as ref. from Press the Set result as ref. from softkey to store the measurement result from the selected channel as the reference level.
Ref. Level Press the Ref. Level softkey to set the reference level value. There is only one reference level for each channel.
Ref. Imp
This is only available for the analog analyzer.
Press the
Ref. Imp softkey to set the reference impedance value. This setting is only available if the unit is set to W and
dBm.
Volt/FS
This is only available for the digital and Bluetooth analyzer.
Press the Volt/FS softkey to set the volts/FS reference value.
Precision
This is only available for the digital analyzer.
Press the
Precision softkey to enable or disable the precision mode.
Cal SPL Press the Cal SPL softkey to set the calibrator level value. This setting is only available when the unit is set to dBSPL.
Freq Lock
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
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 .
Fund Freq
Press the Fund Freq softkey to set the fundamental frequency value. This setting is only available when Freq Lock is set to
Custom.
Analog Notch
This is only available for analog analyzer.
Press the Analog Notch softkey to enable or disable the analog notch filter. This filter is used to emulate the analog notch
filter used in HP8903B.
Table 4-10 Analog/Digital/ Bluetooth Analyzer > Functions > THD+N Level menu description (continued)
Menu Description
20 10 Measured rms voltage
Reference level
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