Roderick Stewart wrote:

In a conversation I had with a friend, we determined that power
cables are good at carrying low frequencies, and poor at carrying
higher frequencies. So RFI picked up at the substation won't make
it to your house, but interference sources in your house will cause
RFI to reach your kit.
How do you determine the electrical properties of cables by
conversation?

By applying known principles of engineering.

The losses at high frequencies are significantly higher in 2.5mm mains
wiring cable than screened co-ax, if you don't believe me try running a
composite video signal down mains cable (rather than 75ohm co-ax) and
see how far you get.

It's like saying "how can you determine that an Audi Quattro is going to
go around a hairpin bend at 100mph faster than a Ford Fiesta", for example.

--
Glenn Richards Tel: (01453) 845735
Squirrel Solutions http://www.squirrelsolutions.co.uk/

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