your question does not contain enough information, for instance the model number, for us to give you the exact answer even if we have it right in front of us. Let me suggest that you try to pin things down to exact details. This might sound really anal, but this is how I always find what I need!
Have you done a google search for the model number of your receiver? (Okay, let me give a detail: that is
www.google.com) Look at the names of the web sites that come up. With some luck, one of them will be the Hughes site and a whole manual may be downloadable.
otherwise, you might run across a dealer whom you could ask about this. They would likely have a web site to refer you to.