Does Anyone Else Have These Old Food Dehydrators?

I remember when I was a kid we used to have all sorts of fun dehydrated fruit snacks that my mom made with this dehydrator.  My mom dug it out from storage and was ready to throw it away when I intercepted it.  I wanted to use it and make delicious healthy snacks for my family.   But something went wrong!

I sliced up my apples and bananas and loaded the tray.  I plugged it in and away it went!  I could hear it humming along.

Throughout the day I kept checking on it and it seemed like it wasn't doing much.  I figured it just needed more time.

12 hours later I took the trays out and it appears that the only thing happened was the fruit browned.  It was still sticky, still gross.  What a waste of a day.

So the question is, did I do something wrong?  I heard it run and it did warm up?  Is there a special trick to the Waring Brand Food Dehydrator from 20 plus years ago?