Stanford Research Systems SR785, Руководство по эксплуатации и программированию

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Playback Input Menu 4-99
SR785 Dynamic Signal Anaylzer
span FFT time records. Normal Speed playback at full span takes 1 second and updates
the display only about 8 times during playback.
Every Time Record playback displays the measurement result for every captured time
record. Since the data is stored in memory, Every Time Record playback is not limited
by real time considerations. For example, 1 second of capture contains 256 full span FFT
time records. In this case, all 256 time records are measured AND displayed. The display
still updates at 8 Hz so playback takes about 32 seconds to complete. If the time records
are overlapped, there may be more than 256 measurements to display and playback will
take even longer.
When the measurement time records are very long (narrow spans), the time to process
and display each measurement is much less than the real time record length. Since the
data is already available in the capture buffer, Normal Speed playback means waiting
unnecessarily for a real time record to elapse between updates. In this case, Every Time
Record playback displays the measurements of all captured time records much faster
than Normal Speed real time playback.
When the playback is in Octave Group, playback is always Normal Speed.
The Capture Progress indicator at the top of the screen shows the playback progress
through the buffer.
Both channels playback with the same Playback Speed.
Command: ISPD (?) {i}