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Creating/editing a .plp file


The 'values' used by PolarPlot

The values used by PolarPlot are relative field strength (E) not relative power. The range is normally from 0 to 1000 (a range of 50dB). The highest value will be placed at the 0dB ring of the plot.

Creating your own .plp file

There may be occasions when you wish to create a  polar diagram for an antenna that cannot be measured using PolarPlot.  This can be done either by creating a CSV (comma separated variables) file using a text editor or spreadsheet, or by typing values directly into the Plp editor screen.

A CSV file should contain one value per record. If the file is created using a text editor (such as Notepad) then this is the equivalent of one value per line; if created using a spreadsheet then this is the equivalent of one value per row in the first column of the spreadsheet.

To display the Plp editor click the 'Show editor' checkbox above the 'Overlay' button. If you close the editor window using the Windows X button at the top right-hand corner of the window, it can be re-opened by un-checking and then re-checking the 'Show editor' checkbox.

To input a CSV file into PolarPlot click the 'Get values from a CSV file' button. A standard Windows File Open dialog will be shown which will enable you to select the desired file. The values in your file are placed in the Plp editor grid.

Instead of reading the values from a CSV file you can type directly into the 'Value' column of the editor grid.

To show the polar diagram, click the 'Update the plot' button.

At any time you may change the data in the editor grid, and re-display the polar diagram.

If you wish to save your data as a .plp file then use the 'Save File' facility described in section 3.8.

Editing an existing .plp file

To display the Plp editor click the 'Show editor' checkbox above the 'Overlay' button. If you close the editor window using the Windows X button at the top right-hand corner of the window, it can be re-opened by un-checking and then re-checking the 'Show editor' checkbox.

The Plp editor screen contains a grid containing two columns of 360 rows. The first column is a reading level, and the second column is an approximate indication of where that reading appears on an un-rotated plot, and taking no account of any readings being trimmed at the front or back of the plot. This position can help you identify which reading is showing where on your screen.

To edit an existing .plp file, first of all show the plot on-screen using the Get File facility. Then click the 'Get values from the plot' button which is on the lower part of the editor screen.  The grid is filled with values from the plot and approximate positions for each reading are shown in the rightmost column.  

Any value may now be edited; or you may insert or delete a row by clicking the appropriate button.  Insert adds a row above the currently selected row; Delete will delete the currently selected row.

When you are ready to see the effects of your changes, click the 'Update the plot' button.

You can clear the grid by clicking the 'Clear all values' button.