In reply to m0unt41n:
Thanks everyone.
In the end I put an aerial in the attic.
After checking the existing there are two separate cables from the roof aerial and each going different ways outside the house and then inside to the kitchen and lounge. So I would have to disconnect these, run a cable from the aerial into the attic to a splitter and a power amplifier and then join two of these back to the original and a third down into the bedroom. I would also have to run a power lead from somewhere to get a socket near the amplifier.
I found instead I could take a cable down through the airing cupboard and then under the carpet and between the underlay and grippers so you cant see it.
The aerial was a Screwfix compact. I can get all the channels OK despite the fact that the transmitter is 50km away and the direction meant that the aerial ended up pointing parallel with the roof ridge line and straight at the gable end wall.
Mind I now hate coaxial plugs and fittings.