Arfa Daily 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.
That actually isn't true. Until recently, when the amateur radio
community, via first the R.A. and then Ofcom, managed to get it
stopped, there were tests of a system call PLT ( power line
transmission ). This system placed RF carriers up to about 30MHz,
onto the domestic mains supply.

This technology actually exists (possibly at a different frequency), and
works very well.

About 18 months ago some student friends asked me if I could get
broadband around their shared house. First thoughts were WLAN of course,
so I duly ordered a broadband account for them, and set up a wireless
router in a central location, with wireless cards in all the PCs and
laptops allowing everyone to access the internet through it.

Unfortunately, it was a rather large house, and there was a huge dead
spot on the ground floor. So... enter HomePlug.

Whacked a HomePlug powerline networking bridge into the router via wired
Ethernet, and plugged a HomePlug access point in on the ground floor in
the middle of the dead spot. Which solved the problem.

All that said, there's no harm at all in helping your kit out by
fitting a surge arrester plug, which contains VDRs, and if you find a
good one, it should have RF suppression in the form of LCR in it, as
well. Worth a tenner for the surge protection at least, and the '
belt and braces ' for the filtering that should already be in your
kit, but I certainly wouldn't pay any more. Even then, I would
probably spend the rest of the week trying to work out if my money
would have been better spent on 4 pints ...

From a purely objective point of view, it's worth spending a tenner (of
a fiver trade) on a surge protected strip to protect 2 grand's worth of
kit, especially if you happen to live somewhere where there's dodgy
power. Yay rural areas...

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

IT consultancy, hardware and software support, broadband installation