var newwindow = ''

function popitup(url) {
if (newwindow.location && !newwindow.closed) {
    newwindow.location.href = url; 
    newwindow.focus(); } 
else { 
	newwindow=window.open(url,'htmlname','width=610,height=530,resizable=0, screenX=300,screenY=300,top=220,left=400');
     }
}

function tidy() {
if (newwindow.location && !newwindow.closed) { 
   newwindow.close(); } 
}