function popup(url){
  popupWindow = window.open (url, 'codes', config='height=500, width=600, toolbar=no, menubar=no, scrollbars=yes, resizable=no, location=no, directories=no, status=no');
   popupWindow.focus()	
}

function OnChange(dropdown,url){
	var myindex = dropdown.selectedIndex
    var baseURL= url
    top.location.href = baseURL + dropdown.options[myindex].value;
    
    return true;
}