In article ,
williamwright wrote:
On 31/03/2021 15:33, Adam Funk wrote:
Similarly, I had an out of use UHF aerial splitter under the floor, that
always floated high enough to give you a good belt, despite the cables
being connected to nothing else!
Well, that's weird.

In 55 years as an aerial installer I never came across such a thing.
Sounds like there actually was a connection to the mains hidden away
somewhere.

Bill

In the analogue days we sometimes got hum on our pictures. Only after it
has been raining, I eventually traced the fault, The 120v on the VCR's
aerial connector found its way to my mast head preamp and then found a path
to ground down the wet wall of the house. This created a 2v drop between
the output and input connections. I earthed the coax outer at the bottom
and the problem went away. The VCR could only provide about 30uA.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle