OTA confusion

[nfusion770]

I just downgraded from a charter digital, to expanded cable- without a box. Tonight I noticed that I failed to run the channel setup for cable (I also have directv). I have a new Olevia 237v which has an internal hd tuner. While scanning for channels it ran a digital and analog search. When it was finished I had about 50 music channels and channels like RF117-1,2,3,4,5,6 and RF119-1,2,3,4,5,6 etc- channels I have never seen before. I know these are OTA channels (some are obviously in HD) but I do not have any sort of external antenna, just basic cable and Directv. These are coming in on the same input my basic cable is plugged into. I assume I'm about 30 miles from most local stations, but I'm certainly picking up my local NBC affiliate in HD.

I am very happy to be picking these up, but have no idea how it's happening. Furthermore, I also have a year and a half old Olevia LT-37HVS (configured with basic cable and DTV as well) that also has an internal tuner, but cannot pick these up.

Anyone want to enlighten and OTA novice on what is going on here? Any clue how I can pick these channels up on my other TV's that have internal tuners?

Enlightenment appreciated in advance- thanks.

[Stewart Vernon]

Newer HDTVs have QAM tuners in them. Many cable systems have unencrypted digital channels (particularly your local channels) that you can pick up without a cable box as long as your TV has a built-in QAM tuner.

If your other TVs are connected to the cable in the same manner, then those TVs must not have a built-in QAM tuner. You can consult your TV instruction manuals to verify. Basically, its a woo-hoo if you have QAM and your cable company has a bunch of stuff in the clear... and not much you can do for those other TVs that don't have the built-in QAM tuner.

[nfusion770]

Never heard of a QAM tuner- makes sense. Appreciate the clarification.

Is there any way to figure out exactly what channels I am getting? A few are obvious, but I have no idea on many of them.

[nfusion770]

Actually the channels at 117 and 119 come and go. From google searches I've determined they could be ppv cable broadcasts or something. The consistent channels are obviously my locals.

[Stewart Vernon]

Generally speaking you should expect to find your local channels (as you obviously have) via QAM from cable. Beyond that who knows. Around here, Time Warner (from talking to people I know with cable) switches things around from time to time, so the channels in-the-clear vary.

Since the channel numbers may vary, and may not match the cable assignment when viewed through a cable box, the only way to find out what channel is what is either to watch for a bit or find someone else in your area on the same cable system who already has figured it out.

Over on AVSForum there are lots of threads for cable/OTA all over the country. You might try looking there and see if there is a discussion about QAM channels over cable in your area as someone may have already compiled a list.