If I wanted to place tv2 of a 322 into my garage, about 80 feet from the receiver, could I use a diplexer and hook it to the tv2 antenna on the receiver and place the antenna in the garage off the other diplexer?
This may be what you're looking for:
http://tech.dishnetwork.com/departmental_content/techportal/Images/Tech/remotes/RemoExtend1.jpg