from a system point of view, simply amplifying the signal by 80 dB does not help that much. What you need to do is amplify ONLY the signal but not the background noise or other TV stations. I once tried to do a receiver for AM radio to pick up a unique station 120 miles away, and found that other stations leaking in were the biggest problem. You want to avoid jammer signals, but improve the signal-to-noise ratio as much as possible
So to start, you need the highest gain TV antenna you can get. and it will be directional, so you need it mounted on a mast with a motor to rotate it to the best position.
Then, right at the antenna, I would add a low noise amplifier. I am going to guess 30 dB would be sufficient, but more might be needed. If you start off with an 80 dB fixed gain, you might saturate the amplifier with other nearby noise, and corrupt the small signal you are trying to receive. Maybe a variable gain low noise amp? or a small gain low noise amp right at the antenna, and another switchable gain amp right at the tv set.
in the above channel power table, you can see that the propagation path for many of the long range tv signals is "tropo", meaning the tv signal is not line of sight, but instead bounces off the troposphere up in the sky. You might need to tilt your high gain antenna up to point more at the sky!