SRS Labs SR850 - Manual (Page 48)

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Use the knob to select 50 nV.
4. Press [TRACE/SCAN]
Press <Sample Rate>
Use the knob to change the sample rate to
16 Hz.
5. Press [DISPLAY/SCALE]
Press <Format> to select Single.
Press <Type>
Use the knob to select Chart.
Press <± Range>
Press [5] [0] [EXP] [-] [9] [ENTER]
Press <sec/Div> (the last softkey).
Use the knob to select 5.0 S/Div.
6. Press [START/CONT]
Wait until the data fills the graph (50 sec) and
data starts scrolling past the left edge.
Press [PAUSE/CONT]
7. Press [MATH]
Press <Stats>
Press <Do Stats>
To measure the input noise, we need to use an
appropriate sensitivity.
Display the Trace and Scan menu.
Since the time constant is 100 ms, we need a
sample rate greater than 1 Hz to record the output.
Choose 16 Hz as the sample rate.
Leave the scan mode on Loop. Data will be
recorded indefinitely with the trace buffer storing
the last 16k (1000 seconds) of data.
Show the Display and Scale menu.
Use a full screen display.
Highlight the display type.
Math functions require a chart display.
Highlight the chart range.
Enter 50 nV for the chart range.
Highlight the horizontal time scale.
Change the scale to 5.0 S/Div so 50 seconds of
data will fill the graph.
Start the scan. The X output is recorded on the
chart display. The chart shows the last 50 seconds
of data. The graph should be a noisy trace about 2
divisions peak to peak.
Pause the data acquisition. No new data is record-
ed and the graph stops scrolling to the left.
Display the Math menu.
Choose the Statistics menu.
The mean, standard deviation, total and time
span are calculated for the data between the left
and right limits. The limits are shown as vertical
heavy dashed lines. The limits default to the left
Trace Math