function showHeader(){
	var now = new Date;
	var timeNow = now.getHours();
	var img = null;
	
	if (timeNow < 6 || timeNow > 21) {
	img = 'logoneon.png';
	} 
		else if (timeNow < 11) {
		img = 'logooff.png';
		}
		else if (timeNow < 18) {
		img = 'logooff.png';
		}
	else {
	img = 'logooff.png';
	}
  document.write('<img src="images\/'+img+'" width="300px" height="200px" alt="Californian Design">');
}