Alternating Headers per page

How do I alternate headers from page to page? I have seen coding on where to put it but I keep receiving error messages.

Here is the code in my header.php

<div id="header">
<div id="logo">
" title="<?php bloginfo('description'); ?>"><img class="title" src="<?php if ( get_option('sdt_logo') <> "" ) { echo get_option('sdt_logo').'"'; } else { bloginfo('template_directory'); ?>/images/logo2.png<?php } ?>" alt="<?php bloginfo('name'); ?>" />
<h1 class="replace">"><?php bloginfo('name'); ?></h1>

</div>