tb1on = new Image(0,0);
tb1on.src = 'images/1b.gif';
tb1off = new Image(0,0);
tb1off.src = 'images/1a.gif';

tb2on = new Image(0,0);
tb2on.src = 'images/2b.gif';
tb2off = new Image(0,0);
tb2off.src = 'images/2a.gif';

tb3on = new Image(0,0);
tb3on.src = 'images/3b.gif';
tb3off = new Image(0,0);
tb3off.src = 'images/3a.gif';

tb4on = new Image(0,0);
tb4on.src = 'images/4b.gif';
tb4off = new Image(0,0);
tb4off.src = 'images/4a.gif';


tb5on = new Image(0,0);
tb5on.src = 'images/5b.gif';
tb5off = new Image(0,0);
tb5off.src = 'images/5a.gif';



rbs1on = new Image(0,0);
rbs1on.src = 'images/vs1b.gif';
rbs1off = new Image(0,0);
rbs1off.src = 'images/vs1a.gif';

rbs2on = new Image(0,0);
rbs2on.src = 'images/vs2b.gif';
rbs2off = new Image(0,0);
rbs2off.src = 'images/vs2a.gif';

rbs3on = new Image(0,0);
rbs3on.src = 'images/vs3b.gif';
rbs3off = new Image(0,0);
rbs3off.src = 'images/vs3a.gif';

rbs4on = new Image(0,0);
rbs4on.src = 'images/vs4b.gif';
rbs4off = new Image(0,0);
rbs4off.src = 'images/vs4a.gif';

rbs5on = new Image(0,0);
rbs5on.src = 'images/vs5b.gif';
rbs5off = new Image(0,0);
rbs5off.src = 'images/vs5a.gif';

rbs6on = new Image(0,0);
rbs6on.src = 'images/vs6b.gif';
rbs6off = new Image(0,0);
rbs6off.src = 'images/vs6a.gif';

rbs7on = new Image(0,0);
rbs7on.src = 'images/vs7b.gif';
rbs7off = new Image(0,0);
rbs7off.src = 'images/vs7a.gif';

rbs8on = new Image(0,0);
rbs8on.src = 'images/vs8b.gif';
rbs8off = new Image(0,0);
rbs8off.src = 'images/vs8a.gif';

dison = new Image(0,0);
dison.src = 'images/11b.gif';
disoff = new Image(0,0);
disoff.src = 'images/11a.gif';

linkson = new Image(0,0);
linkson.src = 'images/12b.gif';
linksoff = new Image(0,0);
linksoff.src = 'images/12a.gif';

function changeImgOn(imgName){

   imgOn=eval(imgName + "on.src");
    document[imgName].src = imgOn;
}

function changeImgOff(imgName){
  imgOff=eval(imgName + "off.src");
   document[imgName].src = imgOff;
}