I had my antenna tv for years. Just this week a group of channels suddely say no signal. How do I fix it

[jamesfitforlife]

Suddenly on my tv using an antenna I lost a group of three channels. It shows them in upper right but says np signal

 

[kanewolf]

Could your antenna have twisted away from the optimal direction? Otherwise, it is probably a coax problem causing low signal. With digital TV it is either all-or-nothing. "Snowy" picture is not a state that digital TV has. You either get a picture or you don't.