Make sure you get an amplified aerial, ie one that has an electrical boost to the signal.
I have experience of this one, and it works well.
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It works best when there is a minimum of brickwork in the way, so if the transmitter is the wrong side of your house it may not work.
For my student youngsters, I found a good way was to hang it from the curtain track behind the curtain. This way it is hardly seen, is quite high, and is behind a pane of glass not a solid wall.