How to use QAM tuner?

What Does a QAM Tuner Actually Do?

• What is the distinction between a QAM tuner and an ASTC tuner? Here's why I ask... as I understand them... if I utilize an ASTC tuner my HDTV finds and uses OTA digital signals and if I need or choose to I must connect the HDTV to a digital antenna, which connects to my HDTV input. With the ASTC tuner I watch available digital signals broadcast over the air. The QAM tuner as I understand it collects and displays for viewing unencrypted signals that are broadcast over cable, which means I must use an existing cable in my home and connect it to my HDTV input. It sounds like while the QAM tuner may be able to collect and display more available channels, I cannot use both at the same time if I choose or need to use an antenna? Please correct any of the above if I am wrong... and my main question is this... if I currently do not subscribe to a cable service (Comcast etc.), can or will the QAM tuner in my new HDTV collect and display unencrypted signals over the existing cable infrastructure in my home. If we are not cable subscribers, is there anything being broadcast over the cable and into our home for us to pick up at all with the QAM tuner? Thanks for your help!

• Answer:

  If you are not a cable subscriber, there is nothing you can receive from your cable wall jack, with one exception. If you are a new resident in that home or apartment, the service from the previous occupant may still be active to some degree--when an account is canceled, the service doesn't necessarily disappear immediately. Failing that, there's nothing for you to see on your cable. You've defined the ATSC and QAM tuners accurately. Since you don't have cable service, the QAM tuner is of no use to you. If you were to subscribe to basic cable (no box), you could make use of it, although doing so would be a bit cumbersome. You'd need to install a simple A-B switch at your TV's antenna jack so that you could conveniently switch from antenna to cable. But you'd have to reset your tuner (between ANTENNA or CABLE) each time you made the change, and you might have to do a fresh channel scan. Also, there is no guarantee that unencrypted digital channels will exist on any cable service indefinitely, nor that every cable service will have any of them at all. Their only requirement at present is to provide local broadcast channels in analog (without a box), and even that ruling has a sundown clause. Bottom line: you're not missing much with a QAM tuner that you can't use.