SRS Labs SR850 - Manual (Page 30)

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4. Press [DISPLAY/SCALE]
Press the <Type/Trace> softkey to select the
Trace number.
Use the knob to select Trace 3.
5. Press [REF/PHASE]
Press <Ref. Source>
Use the knob to select Internal Sweep.
6. Press <Sweep Menu>
Press <Start>
Press [4] [0] [ENTER].
Press <Stop>
Press [1] [6] [0] [ENTER].
7. Press [GAIN/TC]
Press <Time Constant> and use the knob to
select 10 ms.
Press <Synchronous> to select <200 Hz.
8. Press [TRACE/SCAN]
Display the Display and Scale menu. This menu
configures and scales the different screen displays
and graphs.
Highlight the trace number for the Top Bar graph.
The SR850 acquires and displays data in the form
of traces. The default definitions for the 4 traces
are X, Y, R and
θ
. These definitions may be
changed.
Display the magnitude R (Trace 3) on the top
graph.
Display the Reference and Phase menu.
Choose internal reference frequency sweep. In
this mode, the SR850 will sweep the internal oscil-
lator from a start to a stop frequency.
Set the sweep start and stop frequencies in this
submenu. Sweeps may be linear or logarithmic. In
this case, let's use a linear sweep.
Highlight the start frequency.
Set the start frequency to 40 Hz. The reference
changes to 40.000 Hz as shown in the frequency
readout at the bottom center of the screen.
Highlight the stop frequency.
Set the stop frequency to 160 Hz.
Display the Gain and Time Constant menu.
Choose a short time constant so that the frequen-
cy can be swept in a reasonably short time.
Since the sweep frequencies are below 200 Hz,
you can take advantage of the synchronous filter
to remove the 2f component of the output without
using a long time constant.
Display the Trace and Scan menu. This menu
allows the trace definitions to be changed and the
scan (sweep) to be configured. Trace data is sam-
pled and stored in the buffers at the sample rate.
Swept parameters (reference frequency in this
case) are also updated at the sample rate (imme-
diately after the data is sampled). The scan time
Scans and Sweeps