function random_foto() {

  number_fotos=21;
  var now = new Date()
  var sec = now.getSeconds()
  var ad = sec % number_fotos;
  ad +=1;

  url="http://www.dogsite.nl/dogpics.htm";
  alt="Honden fotos";

  if (ad==1) {
     banner="DogPics/dp_dogsite.jpg";
  }
  if (ad==2) {
     banner="DogPics/dp_deslin.jpg ";
  }
  if (ad==3) {
     banner="DogPics/dp_fynn3palmen.jpg";
  }
  if (ad==4) {
     banner="DogPics/dp_bullyscastle.jpg";
  }
  if (ad==5) {
     banner="DogPics/dp_vogelpoel.jpg";
  }
  if (ad==6) {
     banner="DogPics/dp_dieseljack.jpg";
  }
  if (ad==7) {
     banner="DogPics/dp_moonenheidi.jpg";
  }
  if (ad==8) {
     banner="DogPics/dp_teckel.jpg";
  }
  if (ad==9) {
     banner="DogPics/dp_smeets.jpg";
  }
  if (ad==10) {
     banner="DogPics/dp_bullyscastle.jpg";
  }
  if (ad==11) {
     banner="DogPics/dp_nederbels.jpg";
  }
  if (ad==12) {
     banner="DogPics/dp_ofdoubleblack.jpg";
  }
  if (ad==13) {
     banner="DogPics/dp_ofthefirsttriangle.jpg";
  }
  if (ad==14) {
     banner="DogPics/dp_oldhickory.jpg";
  }
  if (ad==15) {
     banner="DogPics/dp_wolfden.jpg";
  }
  if (ad==16) {
     banner="DogPics/dp_robdeboer.jpg";
  }
  if (ad==17) {
     banner="DogPics/dp_shariat-2.jpg";
  }
  if (ad==18) {
     banner="DogPics/dp_utitdoarp.jpg";
  }
  if (ad==19) {
     banner="DogPics/dp_vrienden.jpg";
  }
  if (ad==20) {
     banner="DogPics/dp_wat.jpg";
  }
  if (ad==21) {
     banner="DogPics/dp_zsivanys-1.jpg";
  }


  str="<center>" + "<a href='" + url + "' target='_blank' ><img alt='"+alt+"' src='" + banner + "' border=0 height=80></a></center>";

  document.write(str);
}