What kind of channel (RF) modulator do I need with digital broadcasts?

Question

Do you need a special channel modulator for digital over the air broadcasts? Will some modulators loose audio or video quality, program info or closed captioning?

Also do any modulators exist that will allow you to mix in additional data like closed captioning or program info?

Do the devices typically have a range limit?

As far as I understand as long as the device supports stereo you should be able to get surround sound, is this true? Also is this sound DTS, Pro Logic, 5.1 or 7.1?

Answer 1

The normal way a "modulator" is used is to convert video and audio to an analog RF signal.

Are you asking what type of "receiver" do I need to receive digital TV?  There are many DTV receivers out there and you may even have one built into your TV.  All of them should decode everything on that DTV channel including close captioning, stereo audio, surround etc.

I guess my answer would be you don't need a DTV modulator.  They do exist, but I think they are very expensive and meant for broadcast studios:

http://www.zenith.com/digitalbroadcast/d...

Answer 2

You don't need a special modulator, but you will need a digital tuner, if your  TV doesn't already have one.

This only applies IF you use an antenna to receive local broadcast stations.  If you are using Cable or Satellite for these, then this talk about "digital TV" doesn't apply to you.

Digital tuners are beginning to show up in stores.  You can get a $40 coupon from the government by going to http://www.dtv.gov.

Digital broadcasts will still carry closed-captioning, and will also support SAP (used for bi-lingual broadcasts), and Dolby 5.1 surround - for selected programs.

Digital broadcasting also promises clearer pictures, and new channels.  For instance, the CBS station in my area broadcasts a channel that features live 24/7 local weather and traffic reports, along with headline news.

HD channels are already using digital, but you must have a HDTV in order to watch those.  Most new HDTVs will already contain the new digital tuner, so you won't need a separate tuner.