var objRequest = false; 

function instanceRequest(){ 
  if(window.XMLHttpRequest){ 
    objRequest = new XMLHttpRequest(); 
  }else if(window.ActiveXObject){ 
    try{ 
     objRequest = new ActiveXObject("Msxml2.XMLHTTP"); 
    }catch(e){ 
      try{ 
          objRequest = new ActiveXObject("Microsoft.objRequest"); 
      }catch(e){} 
    } 
  } 

  if(!objRequest){ 
    alert('Es konnte keine XMLHTTP-Instanz erzeugt werden!'); 
    return false; 
  } 
} 


function theRequest() { 
  // Falls noch ein Request-Objekt existiert -> zunächst beenden 
  if(objRequest && objRequest.readyState){ 
    objRequest.abort(); 
    objRequest = false; 
  } 

  if(!objRequest){ 
    instanceRequest(); 
  } 

  objRequest.open('GET', 'signale_abfrage.php', true); 

  self.objRequest.onreadystatechange = function(){ 
    if(objRequest.readyState == 4){ 
      if(objRequest.status == 200){
	  var daten =objRequest.responseXML;
      var text = daten.getElementsByTagName("text")[0].firstChild.nodeValue;
	  var url = daten.getElementsByTagName("url")[0].firstChild.nodeValue;
      document.getElementById(text).innerHTML = unescape(url); 			   			
      }
    } 
  } 
  objRequest.send(null); 
} 

window.onload = function(){ 
    hTimer = window.setInterval(function(){theRequest();}, 1000); 
}