https://www.sd274.com/common/plugins/RadEditorAjax/recorder/recorder.js

1//this is a sample code. Jeong Kyu Eum
2//tool handler function
3Telerik.Web.UI.Editor.CommandList["recorder"] = 
4//function name is not needed.
5function(commandName,editor,oTool)
6{
7    // RadEditor old version using editor.ShowDialog function
8    // RadEditor Ajax version using editor.showExternalDialog function
9    editor.showExternalDialog(
10        "/common/plugins/RadEditorAjax/recorder/AVIRecorderRadAjax.aspx",null,470,500, 
11        //function that is executed when the dialog is closed with the return value.
12        //see Default.aspx file 
13        function(sender, returnValue)
14        {
15            if(returnValue)
16            {
17                editor.pasteHtml(returnValue);
18            }
19        },
20        null,
21        'Recorder',
22        true,
23        Telerik.Web.UI.WindowBehaviors.Close + Telerik.Web.UI.WindowBehaviors.Move,
24        false,
25        true);        
26};