basics for (pre-)filling QSO field

assets/js/sections/qso.js

@@ -286,6 +286,9 @@ function reset_fields() {
 	$('#input_usa_state').val("");
 	$('#qso-last-table').show();
 	$('#partial_view').hide();
+	var $select = $('#darc_dok').selectize();
+	var selectize = $select[0].selectize;
+	selectize.clear();
 
 	mymap.setView(pos, 12);
 	mymap.removeLayer(markers);
@@ -377,6 +380,15 @@ $("#callsign").focusout(function() {
 				$('#hamqth_info').html('<a target="_blank" href="https://www.hamqth.com/'+find_callsign+'"><img width="32" height="32" src="'+base_url+'images/icons/hamqth.com.png"></a>'); 
 				$('#hamqth_info').attr('title', 'Lookup '+find_callsign+' info on hamqth.com');
 
+				var $select = $('#darc_dok').selectize();
+				var selectize = $select[0].selectize;
+				if (result.dxcc.adif == '230') {
+					selectize.addOption({name:'N18'});
+					selectize.setValue('N18', false);
+				} else {
+					selectize.clear();
+				}
+
 				$('#dxcc_id').val(result.dxcc.adif);
 				$('#cqz').val(result.dxcc.cqz);
 				$('#ituz').val(result.dxcc.ituz);