//// variable to store a window object
//var popwin = null;

//// a function to open a pop-up window
//function open_popup()
//{
//  if(popwin == null)
//  popwin = window.open( "pop.html", "","top=100,left=80,width=250,height=100,status");
//} 

//// function to close a pop-up window
//function close_popup()
//{ 
//    if(popwin != null)
//{ popwin.close(); 
//popwin = null; }
//}
var newWindow;

function butOpenWin_onclick()
{
   var winTop = 100
//   (screen.height / 2) - 125;
   var winLeft = 80
//   (screen.width / 2) - 125;
   var windowFeatures = "width=400,height=150,";
   windowFeatures = windowFeatures + "left=" + winLeft + ",";
   windowFeatures = windowFeatures + "top=" + winTop;

   newWindow = window.open("Tips.aspx","myWindow",windowFeatures);
}