<script src="http://code.jquery.com/jquery-1.11.2.min.js"></script>
<script src="http://code.jquery.com/jquery-migrate-1.2.1.min.js"></script>
<script type="text/javascript" src= "https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"> </script>
<script>
	jQuery(document).ready(function(){
		jQuery("#driver").attr("disabled", true);
		jQuery('#select_catalog_typ').change(function()
											 {
			var inputValue = $("#select_catalog_typ").val();
			jQuery.ajax(
				{
					url: 'https://rave-minerals.de/wordpress/wp-content/plugins/PTCR_Web_app/functions_ptcr.php',
					type: 'post',
					data: { 'type': inputValue},
					dataType: 'json',
					success: function (response) //response is value returned from php (for your example it's "bye bye"
					{
						var len = response.length;
						jQuery('#select_catalog_charge')
							.find('option')
							.remove()
							.end()
							.append('<option value="0">- Auswählen -</option>')
							.val('whatever')
						for( var i = 0; i<len; i++)
						{
							var Charge = response[i]["Charge"];
							$("#select_catalog_charge").append("<option value='"+Charge+"'>"+Charge+"</option>");
						}
					}
				});
		});
		jQuery('#select_catalog_charge').change(function()
												{
			var type = $("#select_catalog_typ").val();
			var charge = $("#select_catalog_charge").val();
			jQuery("#driver").attr("disabled", false);
			jQuery('#driver').click(function()
			{
				document.location.href='/wordpress/ptcr-temperatur-generator' + "?type="+type+"&charge="+charge;
			});
		});
	});
</script>
<p>
	Wählen Sie zuerst den Ringtyp aus und anschließend die Chargen-Nr., welche auf dem Ring eingeprägt ist.
</p>
<p>
	Ringtyp:
	<select id="select_catalog_typ">
		<option value="Select">- Auswählen -</option>
		<option value=ETH>ETH</option><option value=HTH>HTH</option><option value=LTH>LTH</option><option value=MTH>MTH</option><option value=STH>STH</option><option value=UTH>UTH</option><option value=ZTH>ZTH</option>	</select>
	
	Charge:
	<select id="select_catalog_charge">
		<option value="0">- Auswählen -</option>
	</select>
</p>
<input type="button" id="driver" value="Daten Laden" />
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