Stanford Research Systems SR780, Operating Manual And Programming Reference

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1-34 Capture
SR780 Network Signal Analyzer
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 124 time
records and takes only 16 seconds to playback
every time record.
12. Press [Input]
Select the Input menu.
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. 123 time records uses 984
kPoints and is close to the full capture length.
Press [9] [8] [4] and [Enter].
Change the Playback Length to an exact number of
time records.
Press [Start/Reset] Start the playback again.
This concludes this example. Capture and Playback
is a way to record a signal and re-analyze it over
and over.