how to make my banners rotate?

i have some original banners in my header

jvazjrsblog.com

i want to add 2 more banners but when i try to add them, they dont show up??

here is my header code for the banners:

<div id=”topright”>
<?
$random = rand(1,7);
echo “<img src=\”http://jvazjrsblog.com/wp-content/uploads/2009/07/JV&#8221;. $random . “.png\” />”;
?>
</div><!– Closes topright –>