Start stop function on scroll event within if/else statement

I have a script which animates a headline. I am trying to make this script fire on page load, but if a user scrolls more than 200px, I'd like this function to stop.

JS:

$(document).scroll(function() {
  var scroll = $(this).scrollTop();
  if (scroll >= 200) {
    $(window).myFunction() return false;
  }
  else {
    $(window).myFunction();
  }
});

What is a better way to do this? Currently myFunction won't fire unless I call it from the debugger in the browser dev tools.