Digital LNB advertiseing is nothing but a Scam, I am a communications electronic engineer. The LNB is designed to receive an analogue signal, amplify by about 60dB, thats a million times! It then converts from 11-12 Ghz down to L band, about 1 Ghz. It has to maintain a good Signal to Noise ratio (not introduce too much noise) and maintain phase integrity so that the receiver can decode the QPSK (quad phase shift keying) modulation. The frequency drift is only significant if it falls outside the sweep range of the satellite decoder. Infact the LNB converts quite a high bandwidth of signals ( Block of transponders), hence the name "Low Noise Block".
This is akin to the digital terrestial aerial Scam, no such thing, the terrestial RF signal is still analogue. The receiver then takes the analogue signal and converts the decoded 0's and 1's to a transport stream (after FEC corrections), the streams consisting of a number of individual channel streams.
So I am afraid that the conception of better pictures is dillusional, a digital stream will go over the "digital cliff" and start to pixelate if the S/N ratio is too high for the FEC circuits to cope with. It either works or it doesn't!
