I'll bet a dollar the DTA does no HD.
The whole point of the DTA is to do for the cableco what the "coupon enabled converter boxes" did for OTA: you get simple reception to your analog TV, in the same square format, from the new digital format as you did by plugging the cable from the wall into the TV when they sent out analog.
What cablecos typically do is send you their exact same lineup as they did with analog, nothing more. The expectation is that they're serving those customers who indeed have analog TVs and who simply plugged the cable in from the wall. The DTA probably has only RF output, for example.
The DTA is a cheap thing, designed specifically to meet FCC mandates and current analog customer requirements. So I'd bet it has only RF out.
TW no doubt has this ALL explained on their support pages, so start there. If not, you can go to this page:http://www.wowway.com/help-support
and look for the link on the right, "Setting Up Your Digital Adapter Is Easy". It's not TW, but it'll give you an idea of what a DTA is.
Oh, wait--I'll be danged:http://www.timewarnercable.com/en/resid ... alcon.html
and there you are.
But before we go farther: what kind of TVs do you have hooked up to STBs now? 'Cuz I'd also be a dollar that the new digital initiative means that they will deliver the channels in clear QAM format instead of analog format, and that a digital tuner will pick up the basic lineup with no converter box needed.
Maybe you didn't even need a STB to begin with? That is, if your TV is new enough and if you get only the standard lineup.
We need more information.