function displayCurrentTime()
{
  var date_obj = new Date();
  var H = '' + date_obj.getHours();
  H = H.length<2 ? '0' + H:H;
  var M = '' + date_obj.getMinutes();
  M = M.length<2 ? '0' + M:M;
  var S = '' + date_obj.getSeconds();
  S =S.length<2 ? '0' + S:S;
  var clock = H + ':' + M + ':' + S;
  document
    .getElementById('hour')
      .innerHTML=clock;
  //"перезапуск"
  var t = setTimeout(displayCurrentTime,1000);
}