if (document.images) {

    nav_01          = new Image(146, 55);
    nav_01.src      = "img/gui/console/01.gif";

    nav_02_on       = new Image(235, 55);
    nav_02_on.src   = "img/gui/console/02h.gif";
    nav_02_off      = new Image(235, 55);
    nav_02_off.src  = "img/gui/console/02.gif";

    nav_03_on       = new Image(247, 55);
    nav_03_on.src   = "img/gui/console/03h.gif";
    nav_03_off      = new Image(247, 55);
    nav_03_off.src  = "img/gui/console/03.gif";

    nav_04          = new Image(142, 55);
    nav_04.src      = "img/gui/console/04.gif";

    nav_05          = new Image(770, 106);
    nav_05.src      = "img/gui/console/05.gif";

    nav_06_on       = new Image(178, 24);
    nav_06_on.src   = "img/gui/console/06h.gif";
    nav_06_off      = new Image(178, 24);
    nav_06_off.src  = "img/gui/console/06.gif";

    nav_07          = new Image(592, 162);
    nav_07.src      = "img/gui/console/07.gif";

    nav_08_on       = new Image(178, 23);
    nav_08_on.src   = "img/gui/console/08h.gif";
    nav_08_off      = new Image(178, 23);
    nav_08_off.src  = "img/gui/console/08.gif";

    nav_09_on       = new Image(178, 24);
    nav_09_on.src   = "img/gui/console/09h.gif";
    nav_09_off      = new Image(178, 24);
    nav_09_off.src  = "img/gui/console/09.gif";

    nav_10_on       = new Image(178, 23);
    nav_10_on.src   = "img/gui/console/10h.gif";
    nav_10_off      = new Image(178, 23);
    nav_10_off.src  = "img/gui/console/10.gif";

    nav_11_on       = new Image(178, 23);
    nav_11_on.src   = "img/gui/console/11h.gif";
    nav_11_off      = new Image(178, 23);
    nav_11_off.src  = "img/gui/console/11.gif";

    nav_12_on       = new Image(178, 23);
    nav_12_on.src   = "img/gui/console/12h.gif";
    nav_12_off      = new Image(178, 23);
    nav_12_off.src  = "img/gui/console/12.gif";

    nav_13_on       = new Image(178, 22);
    nav_13_on.src   = "img/gui/console/13h.gif";
    nav_13_off      = new Image(178, 22);
    nav_13_off.src  = "img/gui/console/13.gif";

    nav_14_on       = new Image(178, 22);
    nav_14_on.src   = "img/gui/console/14h.gif";
    nav_14_off      = new Image(178, 22);
    nav_14_off.src  = "img/gui/console/14.gif";

    nav_15_on       = new Image(592, 45);
    nav_15_on.src   = "img/gui/console/15h.gif";
    nav_15_off      = new Image(592, 45);
    nav_15_off.src  = "img/gui/console/15.gif";

    nav_16_on       = new Image(178, 23);
    nav_16_on.src   = "img/gui/console/16h.gif";
    nav_16_off      = new Image(178, 23);
    nav_16_off.src  = "img/gui/console/16.gif";

    nav_17          = new Image(770, 74);
    nav_17.src      = "img/gui/console/17.gif";

    nav_18          = new Image(254, 58);
    nav_18.src      = "img/gui/console/18.gif";

    nav_19_on       = new Image(240, 58);
    nav_19_on.src   = "img/gui/console/19h.gif";
    nav_19_off      = new Image(240, 58);
    nav_19_off.src  = "img/gui/console/19.gif";

    nav_20          = new Image(240, 58);
    nav_20.src      = "img/gui/console/20.gif";



}

function imgOn(imgName) {
    if (document.images)
        document.images[imgName].src = eval(imgName + "_on.src");
}

function imgOff(imgName) {
    if (document.images)
        document.images[imgName].src = eval(imgName + "_off.src");
}