After a bit of research I believe I have a masthead amp, that requires a power supply at the TV end (which I do not want) (source below).
I do not need VHF or VLF aerial, I just want the UHF. Can I remove the masthead amp and run it straight to the house? Why did my old house (700m away) not need it and the new house does? Is it an old aerial that needs to be replace?
If you are in a weak signal area then you quite possibly will have a masthead amplifier fitted at the aerials which gives you nothing, or extremely weak signals, until you plug in a power supply down in the lounge to power up the amplifier.
So check the "joiner box" up on the aerial mount where the cables from the VHF and UHF aerials combine, then the cable you saw going into the ceiling, feeds out of that box. Open the door and see if you can find a model number printed on the circuit board. If it says "Dip" or "Dipl" then it is a diplexer which just combines the signals and passes then straight out the feed cable, so that won't be your problem.
If it says "MHU" or "MHW" then it is a masthead amplifier and needs a power supply fitted; but there are several different power supplies, (12 volt, 17.5 volt, 22 volt, etc) so you need to fit the correct one or you will blow the masthead unit. So, if it is a masthead amplifier, let us know the brand name (Kingray, Johansen and Ikuzi are the three most popular) and the model number (MHU 23, MHU 24, MHW 34, etc) then we can tell you what power supply you need.
If there isn't a box at all and the cable just goes from the UHF aerial straight down to the wall outlet, then obviously you haven't got a masthead unit, and so you need to check that the cable is actually attached correctly at each end - make sure NONE of the outer shielding is touching the inner core wire at all.