Navigating a spectrum graph

After a spectrum graph is displayed, Grab/Pan mode allows you to scroll vertically and horizontally. To enable Grab/Pan mode, right-click the Spectrum Analysis dialog and choose Grab/Pan from the shortcut menu. A check mark appears next to this option when Grab/Pan mode is enabled. The cursor appears as a hand (), and you can drag horizontally or vertically to scroll through the graph.

When you are zoomed into a selection of the spectrum graph, you can drag the horizontal and vertical sliders to scroll through the graph. The thumbnail image in the lower-left corner of the Spectrum Analysis window will show you which part of the graph is being displayed.

To turn off Grab/Pan mode, choose Grab/Pan from the shortcut menu again.

Changing the graph type

Click the down arrow next to the Normal Display button () and choose Line Graph, Filled Graph, or Bar Graph from the menu to change the type of graph displayed in the Spectrum Analysis window. A check mark is displayed next to the selected graph type.

Note: Some video drivers have problems displaying Filled Graph and Bar Graph modes. If you encounter problems such as incorrect shading or very slow drawing, use the Line Graph option or change video drivers.

If you’re analyzing a multichannel file, you can click the down arrow next to the Normal Display button and choose Single Graph to see all channels in a single graph.

Right-click the graph and choose Logarithmic from the shortcut menu to toggle the x-axis between logarithmic and linear mode. In logarithmic mode, more of the graph is devoted to lower frequencies.

Changing the zoom level of the graph

Zooming can be accomplished in several ways:

1.Drag on the graph to draw a box around the area you want to magnify. You can toggle through mouse selection mode by right- clicking while holding the left mouse button:

•The first type is a vertical zoom window. This will allow you to zoom to a frequency range.

•The second type is horizontal zoom window. This will allow you to zoom to an amplitude range.

•The third type is a combination of vertical and horizontal zoom. This will allow you to zoom to a frequency and amplitude range.

2.Right-click the graph and choose Zoom Out Full to view the entire amplitude and frequency range.

3.Right-click the graph and choose Normalize dB to set the Spectrum Graph amplitude range equal to the maximum and minimum values in the graph.

Synchronizing graphs in a multichannel file

When viewing a spectrum graph for a multichannel file, an individual graph displays for each channel. Click the Sync button () to synchronize the displays so you can view the same region of the FFT in all channels.

Updating a spectrum graph

Select the Auto Refresh button () if you want the Spectrum Analysis display to refresh automatically updated when you change your selection in the data window.

When the button is not selected, the display is not updated until you click the Refresh button ().

If you want the graph to refresh automatically during playback or input monitoring, select the Real Time Monitoring button ().

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