I have 2 cctv cameras which I have set up. The coax from each goes to my loft and then into 2 modulators. Both are set up for quite high channels ( but not the same!!) and then they go into the tv booster/ splitter which feeds 2 tv's. Everything is fine for a few hours and then I lose both cctv images on both tv's. Not at the same time, but within an hour or so of each other. The cameras are fine as I still have a pic on a monitor. If I power down the modulators for 5 mins or so, the pictures come back when powering up. But the same happens again within a few hours. Somewhere between the modulator and both TV's there is obviously a problem ! Its strange that both modulators could be faulty. Can anyone offer some suggestions please ? Many thanks.