求助~~一个页面多个标签转换问题!!

按左边的标签栏，右边那个标签栏就会消失。怎么回事！！？
下面是代码
<style type="text/css">
.s1{display:block}
.s2{display:none;}
table{font-size:12px;}
a.whiteLink:link{color:#FFF;text-decoration: none;}
a.whiteLink:visited{color:#FFF;text-decoration: none;}
a.whiteLink:hover{color:#fff;}
.TechTopNavBar{border-left:1px solid #DDDDDD;border-right:1px solid #DDDDDD;}
.TechSpecialTitle{border:1px solid #DDCE90;background:#FEFFEF;line-height:15px;width:208px;padding-top:2px;text-align:center}.TechBorder3{border:1px solid #C0BBB7;border-top:none}.TechTabActive{width:80px;height:31px;text-align:center;color:#FFF;float:left;line-height:26px;background:url(image/tab_active1.gif);font-weight:bold;cursor:hand;}.TechTabComm{height:31px;text-align:center;color:#605A4E;float:left;line-height:29px;padding-left:12px;padding-right:12px;background:url(image/tab_sline.gif) no-repeat 0px 8px;cursor:hand; }.TechTabComm2{height:31px;text-align:center;color:#605A4E;float:left;line-height:29px;padding-left:12px;padding-right:12px;cursor:hand; }
.TechIndexListTitle{height:24px;line-height:24px;font-size:12px;font-weight:bold}.TechIndexListDetail{line-height:18px;padding-left:5px;color:#666}
</style><script type=text/javascript>
function getObj(objName){return(document.getElementById(objName));}
</script>
<script type=text/javascript>
var num2=8;
function ChangeChannel(module,orderid){
for(var i=1;i<=num2;i++)
{
getObj("Channel"+module+i).className="TechTabComm";
if (orderid>1)
{
getObj("Channel"+module+1).className="TechTabComm2";
}
if (orderid<4)
{
Tempid=orderid+1
getObj("Channel"+module+Tempid).className="TechTabComm2";
}
getObj("Info_"+module+i).className="s2";
}
getObj("Channel"+module+orderid).className="TechTabActive";
getObj("Info_"+module+orderid).className="s1";
}
</script>
</head><body>
<div align="center" class="STYLE3"><span class="STYLE5">标题</span></div>
<table width="728" height="443" align="center">
  <tr>
    <td width="378" height="215"><table width="338" border="0" cellspacing="0" cellpadding="0">
        <tr>
          <td width="391" background="image/tab_bg.gif" bgcolor="#ECECEC">
  <div class="TechTabActive" id="Channel11" onclick="ChangeChannel(1,1);">AAAA</div>
              <div class="TechTabComm2" id="Channel12" onclick="ChangeChannel(1,2);">BBBB</div>
            <div class="TechTabComm" id="Channel13" onclick="ChangeChannel(1,3);">CCCC</div>
            <div class="TechTabComm" id="Channel14" onclick="ChangeChannel(1,4);">DDDD</div></td>
        </tr>
        <tr>
          <td height="180" valign="top" class="TechBorder3"><table width="100%" border="0" cellspacing="0" cellpadding="0" id="Info_11">
              <tr>
                <td>aaaa</td>
              </tr>
            </table>
              <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_12">
                <tr>
                  <td>bbbb</td>
                </tr>
              </table>
            <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_13">
                <tr>
                  <td>cccc</td>
                </tr>
            </table>
            <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_14">
                <tr>
                  <td>dddd</td>
                </tr>
            </table></td>
        </tr>
    </table></td>
    <td width="338"><table width="338" border="0" cellspacing="0" cellpadding="0">
        <tr>
          <td width="391" background="image/tab_bg.gif" bgcolor="#ECECEC">
  <div class="TechTabActive" id="Channel15" onclick="ChangeChannel(1,5);">EEEE</div>
              <div class="TechTabComm2" id="Channel16" onclick="ChangeChannel(1,6);">FFFF</div>
            <div class="TechTabComm" id="Channel17" onclick="ChangeChannel(1,7);">GGGGG</div>
            <div class="TechTabComm" id="Channel18" onclick="ChangeChannel(1,8);">HHHH</div></td>
        </tr>
        <tr>
          <td height="180" valign="top" class="TechBorder3">
  <table width="100%" border="0" cellspacing="0" cellpadding="0" id="Info_15">
              <tr>
                <td>eeee</td>
              </tr>
            </table>
              <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_16">
                <tr>
                  <td>ffff</td>
                </tr>
              </table>
            <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_17">
                <tr>
                  <td>gggg</td>
                </tr>
            </table>
            <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_18">
                <tr>
                  <td>hhhh</td>
                </tr>
            </table></td>
        </tr>
    </table></td>
  </tr>
  <tr>
    <td height="215"><table width="338" border="0" cellspacing="0" cellpadding="0">
        <tr>
          <td width="391" background="image/tab_bg.gif" bgcolor="#ECECEC">
  <div class="TechTabActive" id="Channel21" onclick="ChangeChannel(2,1);">KKKK</div>
              <div class="TechTabComm2" id="Channel22" onclick="ChangeChannel(2,2);">IIII</div>
              <div class="TechTabComm" id="Channel23" onclick="ChangeChannel(2,3);">JJJJ</div>
            <div class="TechTabComm" id="Channel24" onclick="ChangeChannel(2,4);">LLLL</div></td>
        </tr>
        <tr>
          <td height="180" valign="top" class="TechBorder3"><table width="100%" border="0" cellspacing="0" cellpadding="0" id="Info_21">
              <tr>
                <td>kkkk</td>
              </tr>
            </table>
              <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_22">
                <tr>
                  <td>iiii</td>
                </tr>
              </table>
            <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_23">
                <tr>
                  <td>jjjj</td>
                </tr>
            </table>
            <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_24">
                <tr>
                  <td>llll</td>
                </tr>
            </table></td>
        </tr>
      </table>
      
    </td>
    <td><table width="338" border="0" cellspacing="0" cellpadding="0">
        <tr>
          <td width="391" background="image/tab_bg.gif" bgcolor="#ECECEC">
  <div class="TechTabActive" id="Channel25" onclick="ChangeChannel(2,5);">MMMM</div>
              <div class="TechTabComm2" id="Channel26" onclick="ChangeChannel(2,6);">NNNNN</div>
              <div class="TechTabComm" id="Channel27" onclick="ChangeChannel(2,7);">PPPP</div>
            <div class="TechTabComm" id="Channel28" onclick="ChangeChannel(2,8);">OOOO</div></td>
        </tr>
        <tr>
          <td height="180" valign="top" class="TechBorder3">
  <table width="100%" border="0" cellspacing="0" cellpadding="0" id="Info_25">
              <tr>
                <td>mmmm</td>
              </tr>
            </table>
              <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_26">
                <tr>
                  <td>nnnn</td>
                </tr>
              </table>
            <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_27">
                <tr>
                  <td>pppp</td>
                </tr>
            </table>
            <table width="100%" border="0" cellspacing="0" cellpadding="0" class="s2" id="Info_28">
                <tr>
                  <td>oooo</td>
                </tr>
            </table></td>
        </tr>
      </table></td>
  </tr>
</table>
</body>