show-monarch-sidebar-networks-when-scroll.js

// 1st one
<script> 
jQuery(function($) {
    $(window).scroll(function() {
        if ($(this).scrollTop() > 0) {
            $('.et_social_sidebar_networks').fadeIn();
        } else {
            $('.et_social_sidebar_networks').fadeOut();
        }
    });
}); 
</script>

// 2nd one, Another way with JS & CSS

// a) JS
<script> 
jQuery(function($) {
    $(window).scroll(function() { 
        if ($(this).scrollTop() > 500) { 
            $(".et_social_sidebar_networks").css('visibility','visible');   
            $(".et_social_sidebar_networks").fadeIn('slow');  
        } 
        else {     
            $(".et_social_sidebar_networks:visible").fadeOut("slow"); 
        }  
    });
});
}); 
</script>

// b) CSS (Add via Theme Options)

.et_social_sidebar_networks {
 visibility: hidden;
}


// 3rd One, Another way: Only JS

<script> 
jQuery(function($) {
$(window).scroll(function(){
  if($(window).scrollTop() > 500){
      $("#div").fadeIn("slow");
  }
});
$(window).scroll(function(){
  if($(window).scrollTop() < 500){
      $("#div").fadeOut("fast");
  }
});
});