How to uncheck a radio button?

I have group of radio buttons that I want to uncheck after an AJAX form is submitted using jQuery. I have the following function:

function clearForm(){
  $('#frm input[type="text"]').each(function(){
      $(this).val("");  
  });
  $('#frm input[type="radio":checked]').each(function(){
      $(this).checked = false;  
  });
 }

With the help of this function, I can clear the values at the text boxes, but I can't clear the values of the radio buttons.

By the way, I also tried $(this).val(""); but that didn't work.

either (plain js)

this.checked = false;

or (jQuery)

$(this).prop('checked', false);
// Note that the pre-jQuery 1.6 idiom was
// $(this).attr('checked', false);

See jQuery prop() help page for an explanation on the difference between attr() and prop() and why prop() is now preferable.
prop() was introduced with jQuery 1.6 in May 2011.

You wouldn't need the each function

$("input:radio").attr("checked", false);

Or

$("input:radio").removeAttr("checked");

The same should also apply to your textbox:

$('#frm input[type="text"]').val("");

But you could improve this

$('#frm input:text').val("");