Trace Properties

Trace properties control the visual appearance of the displayed traces (lines, markers) as they appear on the screen while sweeping and after its completion (the two cases may slightly differ). To start modifying trace properties, you can do any of the following:

• Click the toolbar button.

• Right-click the Legend panel of the display window you wish to modify.

• Click the Trace|Properties menu item (this affects the properties of the currently active display window).

A dialog box titled Trace Properties appears (Fig. 18). The dialog contains three panels, titled Visible Traces, Line, and Markers. The topmost panel also includes a preview box.

Fig. 18.  Trace Properties dialog box.

To modify Trace properties, proceed as follows:

Visible Traces Panel

The Power and LogPower plots may display up to three traces: incident, reflected, and absorbed power. In the checkbox list on the left, select which traces you want to be visible on the graph, and in the adjacent dropdown menu, select the trace you wish to edit.

For the remaining plots (Mag, Polar, VSWR, etc.), only one trace is available for editing and it is automatically selected.

The right portion of the panel shows the preview of the trace currently being modified.

Line Panel

Check the Visible checkbox if you want the measured points to be connected by a straight line. Select the color, width (in pixels), and style of the line. Note that when the width is greater than one, only solid line will be drawn.

Markers Panel

The Markers panel defines whether and how the markers (dots) for each measurement point will be displayed during the sweep and afterwards. This also depends on the state of the Persist checkbox (see below). For now, suppose the Persist box is unchecked.

Visible

The Visible checkbox decides whether the markers will be drawn after completing the sweeping. For the behavior while sweeping, see the description of the Moving checkbox.

Moving

When the Moving checkbox is checked, a single point is shown on the trace running as the sweep progresses. During sweeping, this happens regardless of the Visible checkbox state. After stopping measurement, the trace is updated depending on the Visible status as follows:

• If Visible is checked, the complete trace is shown, including all markers.

• If Visible is unchecked, the markers are not displayed.

When the Moving checkbox is unchecked, the trace, both while sweeping and afterwards, is drawn with or without all markers depending on the Visible state.

Pixels

When the Pixels checkbox is checked, a single dot (pixel) with the color equal to the Line color is left behind at each measurement point in addition to anything else. You may wish to combine it with Moving Point in circular plots.

Marker Appearance

The marker appearance and size are defined by the rest of the controls in the Markers panel. It is best to try it out and see. Line Width affects only the thickness of the following three markers: + ´ *.

Other Controls

Persist

When the Persist checkbox is checked, the display acts as an oscilloscope with infinite persistence, not erasing previous traces as the new trace is being drawn while sweeping. In this way, glitches, e.g., temporary irregularities, and measurement history can be captured.

Note, however, that this has only a volatile nature: resizing the display window clears all accumulated traces, leaving only the final sweep.

The Persist function is also accessible from the Trace|Persist menu item or the display window toolbar button .

If the Persist is ON the traces are displayed with or without markers depending on the Visible checkbox state. The setting of the Moving checkbox is irrelevant.

Clear and Go

When Clear and Go is checked, the display is cleared before start of each measurement. In this way, only one set of traces at a time is displayed (like an oscilloscope). When the checkbox is unchecked, the contents of the display are left unchanged and new traces are just added. In this way, more curves can be displayed simultaneously and visually compared.

As with Persist, this has only a volatile nature: resizing the display window while Clear and Go is unchecked clears all accumulated traces, leaving only the final sweep.

The Clear and Go function is also accessible from the Plot|Clear and Go menu item or the display window button .

Tips for Circular Plots

Three useful settings for circular plots are:

Panel	Control	Setting 1	Setting 2	Setting 3
Line	Visible			ü
Markers	Visible
Markers	Moving	ü	ü	ü
Markers	Pixels		ü

Setting 1 provides only one marker “flying” over the plot, corresponding to the current measurement point.

Setting 2 provides a flying marker like in Setting 1 plus a dot (pixel) for each previous point, enabling the user to see the history from the start of a sweep.

Setting 3 provides a comet-like picture: a flying marker like in Setting 1 plus a line tail representing a number of previous points, enabling one to see the recent history. The number of points in the tail is equal to the number of currently selected points per sweep. Points per sweep can be defined by Homer|Points per Sweep, the  Pts  toolbar button, or the Ctrl+N shortcut.