I have seen on many shows that they are Simucast in HDTV and I was wondering if you had a HDTV compatible in your TV did you need anything else to watch those shows in HDTV, thanks.
Unless your TV has a built in HD tuner, you also need an HD receiver to view these shows. In addition, the station has to be broadcasting HD in your area either over the air or by a satellite system.
You need an HD-ready set and a separate HD tuner box, either over-the-air or a cable box if your local cable system is offering HD, or a set with an HD-tuner built in.
With the ota box or set with built-in-tuner, you'll also need an antenna--either indoor or outdoor depending on reception conditions in your area.
And last but not least, the local affilliate for the network carrying the show in HD has to have a digital signal up and running and be capable of passing the HD signal from the network. While most all local network affilliates in the US are now capable of digital broadcast, not all are capable of passing the HD version from the networks.