You need 2 coax runs from the Dish to the DVR, and just one connection (HDMI or component) to the HDTV.joshjr said:
If you have more than just that one unit, they will most likely install a multiswitch between the dish and the endpoint at your DVR.
You can watch 1 channel and record another at the same time, or else record 2 channels at the same time. Recoding can be set even with the HDTV turned off completely.
Enjoy.