118 Chapter 3
Making Measurements
Audio SINAD Measurement
Step 6. To adjust the measurement settings, press Meas Setup, then:
1. To change the average number between
On and Off, press the Avg Number key.
When setting to
On, enter the number. The default average setting is Off and the
default number is 25 when switching to
On. When the input signal is changed
during the average period, wait until the averaging is done or the next
averaging period starts.
2. To change the average mode, toggle the
Avg Mode key between Exp and
Repeat. The default average mode is Repeat.
Step 7. To adjust the display, press
AMPLITUE/Y Scale, then:
1. Press the
Display Unit key and select a display unit key. The default
setting is
dB.
2. Press the
Display Mode key to toggle between Normal and Ratio. The default
setting is
Normal.
3. Press the
Ratio Ref key to toggle between Auto and Man. When you select Man,
input the reference value and unit. When the reference is set to 0 or the
measurement result is 0 under log ratio mode, the result displayed is “- - -”.
4. Press the
Ratio Mode key to toggle between Log and Linear.
Audio SINAD Measurement Example
Figure 3-27 Audio SINAD Measurement Result
Signal Under Test:
Audio Frequency: 1000 Hz; Amplitude: 1 Vp; Modulation: Off.
In this example, the measured Audio SINAD is 73.189 dB.