Stanford Research Systems SR785, Руководство по эксплуатации и программированию

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1-32 Capture
SR785 Dynamic Signal Analyzer
Use the knob to select (Manual) and press
[Enter] Each manual Trigger will step one time record into
the capture buffer.
Press <Manual Trigger> several times Each time record is 1k points long, or represents
.11% of the 900k capture buffer. Note that the
playback indicator increments by .11% each time
<Manual Trigger> is pressed.
Press <Trigger Source>, select (Cont) with the
knob and press [Enter]. Return to continuous playback.
11. Press [Freq]
Select the Frequency menu.
Press <Span> Change the measurement span. The span can not be
increased above 51.2 kHz since the captured data is
bandwidth limited to 51.2 kHz (because of our
capture sampling rate).
Use the knob to select (6.4 kHz) and press
[Enter]. Change the span to 6.4 kHz.
Capture playback allows the same captured data to
be measured at different spans, windows,
averaging, etc. This is useful if the signal is hard to
reproduce or occurs infrequently.
Press [Start/Reset] At this span, the capture buffer only holds 112.48
time records and takes only 14 seconds to playback
every time record.
12. Press [Input]
Select the Input menu.
Press <Playback Config> Enter the playback configuration submenu.
Press <Playback Length> It is generally a good idea to playback an exact
number of time records. This way, the last record
doesn’t wrap around and use points from the start
of the buffer.
At this span (with no overlap), each time record is
62.5 ms long. The capture sampling rate was 131.1
kHz so 2 kPoints of capture represents 15.625 ms
of data. Thus each time record is 8 kPoints of
capture long.
We want the Playback Length to be an integer
multiple of 8 kPoints. 112 time records uses 896
kPoints and is close to the full capture length.
Press [8] [9] [6] and [Enter]. Change the Playback Length to an exact number of
time records.
Press [Start/Reset] Start the playback again.