Specifications

Figure 23

The center of the upper display is the main trace with a narrow black window around the section of the

main trace that is expanded in the delayed sweep, the lower trace. The "Z" shows that the delayed

timebase is set to a sweep speed of 500 ns/div, or 400 times faster than the main timebase. Thus,

we're able to see much more detail in the waveform.

The delayed sweep may be able to show you things not easily seen with the main timebase. For

example, if you display a 1 kHz square wave, the delayed sweep can show you the jitter in the position

of the square wave's edges (switch to real-time sampling to see it). You can use the horizontal position

adjustment to measure the width of the envelope of the jitter by positioning the envelope over a vertical

graticule.

XY display mode

This feature is nominally the same as the XY display mode of an analog scope.

Saving waveforms and data

Saving a waveform is a valuable feature that analog scopes don't have. There are two primary ways

this can be done: a computer program can download the digital information from the scope or the scope

can store the waveform on a flash drive.

A computer program like WaveXpress® can download the currently displayed waveform from the

oscilloscope, display it, and transform it in a variety of ways.

Saving a waveform to a flash drive is done by inserting a flash driven into the USB jack on the front

panel of the scope. On the B&K 254xB scopes, The Utility button can be pressed and the Print Setup

menu accessed to determine what file type will be saved when the Print button is pressed. The choices

are CSV (comma separated values, an ASCII data file format that can be imported by a spreadsheet),

8-bit BMP, 24-bit BMP, GIF, and PNG. The last four are bitmap image formats. When a flash drive is

plugged into the scope and the Print button is pressed, the screen image is saved in the chosen format

(the file name is automatically chosen; subsequent saves increment a number in the file name).

Copying/reprinting/republishing without express written consent prohibited.