BLP,
<body>
<select name="PB2001" onchange="fifeno(this)">
<option value="?">?</option>
<option value="no">no</option>
<option value="(BG) NFF LO">(BG) NFF LO</option>
<option value="(BG) NFF RX">(BG) NFF RX</option>
<option value="(AT) KKO LO">(AT) KKO LO</option>
</select>
<input name="input" id="input" value="Появился1">
<input name="input2" id="input2" value="Появился2">
<script type="text/javascript">
function fifeno(self) {
var input=document.getElementById('input'), input2=document.getElementById('input2');
switch (self.value) {
case "no": { input.style.display = "block"; input2.style.display = "none"; break; }
case "?": { input.style.display = "none"; input2.style.display = "none"; break; }
default: { input.style.display = "none"; input2.style.display = "block"; break; }
}
}
</script>
</body>