I don't think you need a big dish. I'm getting 12dB on the French channels and around 9.5 - 10dB on the Italian ones - so if you can see RAI, then you should be getting sufficient signal on TF1 etc. Maybe it's the fact that the French channels are multistreamed? I don't know if the RAI channels are also multistreamed. What box and tuner are you using? The LNB wouldn't be relevant as regards multistreamed - it's the tuner.