uncheck all radio buttons in jquery

function uncheckAll()
{
allChk = document.getElementByType("radio");
     for (i = 0; i < allChk.length; i++)
        {
        document.Form1.allChk[i].checked = false;
        }
}

function uncheckAll()
{
allInp = document.getElementByTagName("input");
for (i = 0; i < allInp.length; i++)
{
  if (allInp[i].type == "radio")
  {
    allInp[i].checked = false;
  }
}
}

$("input:radio[name='thename']").each(function(i) {
       this.checked = false;
});