var myID = '012_Terouma-5770';
var myFile = 'http://www.torah-box.com/chavoua-tov/pdf.php?file='+ myID +'.pdf';

document.write('<div style="background-color:#eee;padding:1px;width:150px;text-align:center;margin:10px auto 10px auto">');
document.write('<a href="'+ myFile +'" target="_blank"><img src="http://www.torah-box.com/chavoua-tov/'+ myID +'.jpg" border="0" alt="Cliquez-ici pour télécharger Chavoua-Tov"/></a>');
document.write('</div>');