function ri4techSwitch(index) {
    document.getElementById('s1').style.display = (index == 1) ? 'block' : 'none';
    document.getElementById('s2').style.display = (index == 2) ? 'block' : 'none';
    document.getElementById('s3').style.display = (index == 3) ? 'block' : 'none';
    document.getElementById('s4').style.display = (index == 4) ? 'block' : 'none';
    document.getElementById('s5').style.display = (index == 5) ? 'block' : 'none';
    
    if (window.event)
        window.event.returnValue = false;
    return false;
}