There are a few problems with trying to use a DBS dish for Ku. First, its really too small. Ku is lower power than DBS, so you need at least a 30" dish to get most of what's up there. Secondly, DirecTV (or Dish Notwork) dishes use DBS LNBFs, which are designed to receive circular-polarized signals. Ku satellites (which most FTA is on) use linear-polarized signals, so you'd have to replace the DBS LNBF with a linear Ku LNBF that would fit the DirecTV dish's D-mount (most won't without rigging up a holder). Finally, since you'd be receiving linear signals, you'd have to find a way to skew the LNBF for any satellites a bit east or west of directly south from your location.