Sounds like bad cable connection or cable, since it goes down but then comes back up..could be a bad LNB or poor alignment also..many things are possible..
Is there more that U are NOT telling us like U have switches and dual or twin LNB with 2 outputs, or another dish or LNB's all connected also..U need all the info before U can do a diagnosis of your problem a problem
Sounds like bad cable connection or cable, since it goes down but then comes back up..could be a bad LNB or poor alignment also..many things are possible..
Is there more that U are NOT telling us like U have switches and dual or twin LNB with 2 outputs, or another dish or LNB's all connected also..U need all the info before U can do a diagnosis of your problem ..