HP 54540 Series - Making Automatic Measurements from the Front Panel

Measurements
Making Automatic Measurements from the Front Panel
Making Automatic Measurements from the Front Panel
The oscilloscope makes its measurements using the data showing on the
display (except for At measurements in the real-time mode). Therefore, it is
important that you correctly window the display to get accurate
measurements. Windowing allows you to pick one pulse out of a series of
pulses to make measurements on.
If more than one waveform, edge, or pulse is displayed, automatic time
measurements are made on the first (leftmost) portion of the displayed
waveform that can be used. Voltage measurements, like Vp-p, use the whole
waveform
When making measurements on non symmetrical waveforms, expand the
signal as necessary and move the baseline out of the window. This will avoid
having the baseline selected as the top of the signal.
If the signal is clipped, the oscilloscope cannot make some automatic
measurements. You will get a warning or error message if this occurs.
If the measurement window is set to markers, the measurement is made on
the data between the X1 and X2 markers.
Period and Frequency Measurements
At least one full cycle of the waveform, with at least two like edges, must be
displayed for period and frequency measurements.
Additionally, you can increase the accuracy of frequency measurements by
windowing on multiple pulses. Automatic waveform measurements use a
single pulse and may have significant errors introduced by interpolation. By
placing marker 1 on edge 1 and marker 2 on edge 20, for example, you can
get an average that negates errors that may be introduced in automatic
measurements. This becomes even more important when using the deep
memory feature of the oscilloscope.
Set the markers to accomplish average frequency measurements from the
front panel by using the At measurement in the define measure menu.
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