images = new Array(6);
images[0] = "<img src='random/sennheiser.jpg' >";
images[1] = "<img src='random/novo.jpg' >";
images[2] = "<img src='random/radiometer.jpg' >";
images[3] = "<img src='random/lattec.jpg' >";
images[4] = "<img src='random/ibsen.jpg' >";
images[5] = "<img src='random/bluelab.jpg' >";


index = Math.floor(Math.random() * images.length);
document.write(images[index]);