Scambiare valore radiobutton da popup a finestra principale

[Xinod]

function valore(){
  var rds=document.form1.R1, l=rds.length, val='';

  if(l>1){
    for(var k=0;k<l;++k){
      if(rds[k].checked==true){
        val=rds[k].value;
        break;
      }
    }
  }
  else {
    val=rds.value;
  }
  window.opener.document.forms['newform'].testo1.value=val;
  self.close();
}