var imgs1 = new Array("/img/transport_owg_top.jpg","/img/kipper_owg_top.jpg","/img/transportbegeleiding_owg_top.jpg","/img/tanktransport_owg_top.jpg");
var alt1 = new Array("banner1","banner2","banner3","banner4");
var currentAd1 = 0;
var imgCt1 = 4;
function cycle1() {
  if (currentAd1 == imgCt1) {
    currentAd1 = 0;
  }
var banner1 = document.getElementById('header_rotator');
  banner1.src=imgs1[currentAd1]
  banner1.alt=alt1[currentAd1]
  currentAd1++;
}
  window.setInterval("cycle1()",4000);