On Mon, 18 Jun 2007 22:22:04 +0100, John Rumm
wrote:

:Jerry: wrote:
"John Rumm" wrote in message
...
snip
You could also use "home plug"
devices to do away with the data wire and route the network over the
mains instead.


How does those network systems avoid sending the data down the 'ring
main' in the street, is their something about elecy meters that
prevent such transmitting of data or does it work by encrypting the
data like (a correctly set up) wireless system?

They claim to not get out of the property past the meter, but I am not
sure if there is any technical reason for this, or if it just comes down
to range. They do have encryption, and you can group a number of them
into a private network.

I'd have thought that the current-measuring bit of the meter would
have had sufficient inductance to effectively block most of the RF
applied to the line downstream of it.

If you have a section of SWA there's likely enough capacitance between
the conductors and the armour wires to limit the performance at RF.

You really have to take an entirely RF-based (capacitance/inductance)
assessment of your installation as well as the power-based stuff.

--
Frank Erskine
Sunderland