A Slingbox Pro sends the TV signals received at its physical location out onto the Internet. You can then watch those programs on a computer connected to the Internet in another state. The way I am able to currently watch those programs on a TV in that other state is to connect my TV in that other state to my computer in that other state -- my TV has the capability to be, in effect, an external or second monitor for my computer, with a simple VGA cable connection.
I don't subscribe to HD TV services where my Slingbox is located, so the Slingbox only sends programs to the Internet in Standard Definition. So, although the TV that I connect to my computer in the other state IS an HD TV, it will only display the programs coming from the Slingbox in Standard Definition.
Others reading this forum many provide tips on how to display these programs in HD on your TV in another state.