LeCroy 9300C Series, Руководство оператора

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10 –1
Zoom, Mathematics and Math Setup
10
Zooming for Precise Waveform
Measurements
Several traces can be zoomed from a single waveform to
obtain precise timing measurements.
For instance, on a waveform composed of two pulses separated
by a long delay, Trace A could be made a zoom of the first
pulse, and Trace B a zoom of the second.
The combination of long memory and zooming allows extremely
accurate time interval measurements. And the time resolution
on the viewed trace can be significantly improved.
For example, choosing 50 000 points per channel on a timebase
of 0.1 ms/div, traces can be expanded to as much as 50 ns/div
— a factor of 2000. Using Relative Time
cursors ( see Chapter
14 ), a delay of, say, 500
µ
s could be measured with resolution
as high as 0.5 ns. Even with as many as eight million points
acquired, zooming can be done until there are only a few points
on the screen.
Using Multi-Zoom
With Multi-Zoom, the zoomed region of the waveform can be
moved simultaneously along two or more different traces, or two
or more regions of the same trace.
When “Multi-Zoom” “ On ” is selected from the “ZOOM – MATH”
menu ( see page 10–8 ), the horizontal zoom and position
controls apply simultaneously to all displayed traces — A, B, C
and D — allowing similar sections of different traces to be
viewed at the same time. The vertical controls still act
individually on the traces: switching from one trace to another is
done using the TRACE ON/OFF buttons. The highlighting of
trace titles in the Displayed Trace label indicates an active Multi-
Zoom.
Zooming Math Functions
When Trace A, B, C or D is defined as a mathematical function
rather than as a simple zoom (
see next section ), the zoom controls
remain operative and defining another trace as a zoom of the math
function becomes unnecessary. In order to view the entire