You can down load a manual
HERE . Note there is one for pre 2009 and one for post 2009.
You can see some info on it
HERE
Although the site says you can get limited HD from Direct TV on satellite 119, I think that is out of date.
I think all HD is now on the 99 and 103 KA band satellites which the unit will not pick up. That is also what the comparison chart down the page says.