HP 1652B Getting Started Manual page 488

B
Automatic Measurement Algorithms
Introduction
Measurement
Setup
,-
Making
Measurements
HP 16528/1653B
Front-Panel Reference
One of the HP 1652B/1653B's primary oscilloscope features is its
ability to make parametric measurements. This appendix provides
details on how automatic measurements are performed and some tips
on how to improve automatic measurement results.
Measurements typically should be made at the fastest possible sweep
speed to obtain the most measurement accuracy possible. For any
measurement to be made, the portion of the waveform required for
that measurement must be displayed on the oscilloscope:
l
At
least one complete cycle must be displayed for period or
frequency measurements.
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The entire pulse must be displayed for pulse width measurements.
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The leading (rising) edge of the waveform must be displayed for
risetime measurements.
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The trailing (falling) edge of the waveform must be displayed for
falltime measurements.
If more than one waveform, edge, or pulse is displayed, the
measurements are made on the first (leftmost) portion of the displayed
waveform that can be used. When any of the defined measurements are
requested, the oscilloscope first determines the top (100%) and base
(0%) voltages of the waveform. From this information, it can
determine the other important voltage values (10% voltage, 90%
voltage, and 50% voltage) required to make the measurements. The
10%
and 90% voltage values are used in the risetime and falltime
measurements. The 50% voltage value is used for measuring
frequency, period, pulse width, and duty cycle.
Automatic Measurement Algorithms
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