Unless the HD tuner is made to receive cable channels, it won't work. You might get a few, the low channels that use the same band as OTA channels. Most cable channels use a different band than OTA channels, so a receiver made for OTA channels won't work. You can use a VCR or DVD recorder tuner though.
Well running basic cable through the hd tuner does not work. It couldn't find any channels. So I need to get something that will take in a coax cable and have outputs for the 3 color cable I'm using to go to the hdtv. I have no idea if anything like that is even made. Does anyone know?