I just purchased the HD DVR HR-21 and I am waiting for my 5 LNB slimline dish to arrive, if I were to activate the HR-21 would I be able to operate it off of the 3 LNB dish until I get my 5 LNB dish next week? Also would it be able to pick up any HD channels, I really just want to test it out and see some high def while I wait??????