if (document.images){

broadcast_button_on = new Image();
broadcast_button_on.src = "images/lnav_broadcast_off.gif";
broadcast_button_over = new Image();
broadcast_button_over.src = "images/lnav_broadcast_on.gif";

oped_button_on = new Image();
oped_button_on.src = "images/lnav_oped_off.gif";
oped_button_over = new Image();
oped_button_over.src = "images/lnav_oped_on.gif";

press_button_on = new Image();
press_button_on.src = "images/lnav_press_off.gif";
press_button_over = new Image();
press_button_over.src = "images/lnav_press_on.gif";

print_button_on = new Image();
print_button_on.src = "images/lnav_print_off.gif";
print_button_over = new Image();
print_button_over.src = "images/lnav_print_on.gif";

}