function channel_spacing_help_rf(Pll_name, Type) {

   var vcomin 	= document.mainform.rf_vcomin.value;
   var vcomax 	= document.mainform.rf_vcomax.value;
   var xtal	= document.mainform.xtal.value;
   var random = Math.round(Math.random() * 100000);

   var nextURL 	 = '/appinfo/webench/EasyPLL/help/ChannelSpacing.cgi?';
   nextURL     	+= 'vcomin=' + vcomin;
   nextURL	+= '&vcomax=' + vcomax;
   nextURL	+= '&xtal=' + xtal;
   nextURL	+= '&Pll_name=' + Pll_name;
   nextURL	+= '&Type=' + Type;

   var h_size;
   if (parseFloat(vcomin) == parseFloat(vcomax)) {
      h_size = 600;
   } else {
      h_size = 400;
   }

   popWindow = window.open(nextURL,random,'toolbar=yes,history=no,location=no,scrollbars=yes,resizable=yes,width=500,height=' + h_size);

}