elpenguino:
Hmm. Sorry, that does point towards an adequate aerial but poorly shielded coax.
You might have to work on mitigation strategies.
And there's not much good on telly these days anyway.
Ah well, I tried (also tried twisting the power cables and wrapping foil around those too, which might have given a slight improvement from what I can see using the signal numbers on the TV).
The only live TV that we watch is The Chase and the 6PM news, everything else is streamed. I guess for the times that we're using the fan we'll just have to stream those two programmes.
Thanks everyone for your help!
