MS400 datasheet(21/51 Pages) EXTECH

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MS400 Version 2.0 – December 2007

Term Glossary

Collecting mode:

The oscilloscope transforms the collected analog data into a digital

form after it is gathered in the following three modes: sampling, peak value detection

and averaging values.

Sampling:

The oscilloscope takes samples from the signal at equal time intervals to

reconstruct the waveform. In this mode, the analog signal can be expressed correctly

in most cases. However, rapid changes cannot be detected between two sampling

time intervals.

Peak value detection:

The oscilloscope takes samples from the maximum and

minimum of signals in each sampling interval and shows the Waveform with the

sampled data. Thus, the oscilloscope may capture narrow pulses that could not be

detected in sampling mode.

Averaging values:

The oscilloscope collects several Waveforms, averages them,

and displays the averaged Waveform. In this mode random noise can be reduced.

Duration time:

When a new Waveform is displayed, the previous Waveform shown

on the screen does not disappear immediately but will continue to be displayed for a

period of time. This period of time is referred to as the duration time. Thus, a display

similar to that shown by an analog oscilloscope can be achieved.

Roll scan mode:

The oscilloscope updates the Waveform sampling points by

scrolling through the screen from left to right (only applicable to the primary time base

setting above 50ms).

Selecting AC-Coupling

After a reset, the Oscilloscope is dc-coupled so that ac and dc voltages appear on the

screen. Use ac-coupling to observe small ac signals that ride on a dc signal. To select

ac-coupling:

1. Press the MENU key and the function menu will appear at the right side of the

screen.

2. Press the MENU UP or the MENU DOWN key to select the CH1 SETUP. Four

selectable items are visible at the bottom of the screen.

3. Press the F1 key and jump to AC. The bottom left side of the screen displays the ac-

coupling icon.

The user can view a screen that looks similar to the following Figure 17.

Figure 17: AC-Coupling

MS400 Datasheet(PDF) 21 Page - Extech Instruments Corporation.