You can use these steps to display multiple plots in a single window.
1) Make sure you're in "Historical Data Analysis" mode from Motion Amplification Settings
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2) Create a "Collection"
3) Create a Measurement Location under the Asset. Select the Asset level Icon and either Right-click to reveal a pop-up menu or use the top ribbon toolbar and select "New Measurement Location".
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4) Move the recordings you want to "historize" into the Collection
5) From the appropriate window - Spectrum or Waveform - right-click and select "Attach Waveform to>Current Collection (Measurement Location)".
6) Once you have all the items added to the Collection/Measurement Location, you'll be able to select and add them to Waterfall Plots by using the "Navigation" pane.
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You'll see this message the first time you open the Navigation Panel and it gives a "very brief" explanation.
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When you have a recording open and you click on the "Waterfall" icon, highlighted with the green box below,
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you'll get a Waterfall that includes ALL of the plots you have "checked" from the Navigation pane.
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