function on_change_city_filter(cityid) {

	dropdown = document.getElementById('display_rec_type')
	var myindex  = dropdown.selectedIndex
	var SelValue = dropdown.options[myindex].value
	var base_URL = 'view_info.php?city=' + cityid + '&cat=' + SelValue;
	if (SelValue != 'none'){
		top.location.href = base_URL;
	} // end if...then

} // end function on_change_city_filter