Possible Setup Issues
During remote operation of the Audio Analyzer, you should always set the Trigger Arm to Single. The length of time required to return a measurement over GPIB using continuous triggering varies, but is always longer than when using single triggering. Continuous triggering can also cause problems when the INITiate:DONE? query is used.
The Detector Type selected (peak or rms) also sets how Audio Level measurements are displayed; as a peak value or an rms value. When comparing returned values over GPIB to your specifications, be sure to take into account the type of detector being used.
The Expected Peak Voltage is always set in V
peak
, regardless of the Detector Type selected, and cannot exceed 20 V
peak
(14.1 V
rms
).
For accurate measurements, always set all Audio Analyzer setup parameters to their proper settings for the measurement being made. The SINAD and Distortion measurements typically use different settings than the Audio Level measurement. See
Audio Analyzer Measurement Description
and
Audio Analyzer Block Diagram
.
For very low level audio signals, use the 100 Hz BW BPF filter to reduce the affects of noise (see
Audio Level Measurement Description
).
For accurate Audio Frequency measurements where more than one signal may be present, use the 100 Hz BW BPF filter to isolate the desired signal (see
Audio Level Measurement Description
).
Interpreting Integrity Indicator Values
See
Integrity Indicator
.
If over range (5) is returned, the input level is greater than 4.9 dB above the Expected Peak Amplitude value or the maximum input level of 20 volts peak.
If under range (6) is returned, the input level is lower than 8 dB below the Expected Peak Amplitude value.
If the signal has both over range and under range conditions, only the over range condition (5) is indicated.
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