Michael Chapman wrote:
Anyway if anyone knows of a
wireless cable system out there that is high quality and works over
distances of up to 400m (in places where there is no internet) please let
me know !
You can (or could) get little boxes that plugged ino power points (as in
220v sockets) that each had an (?)ethernet* socket.
A sort of poor man's WiFi for in the home ... except they weren't that cheap.
Powerline communication (PLC), right?
But help, they have used powerlines for radio transmition,. a
loooooooong time ago.
http://en.wikipedia.org/wiki/Carrier_current
Carrier current is a method of low power
<http://en.wikipedia.org/wiki/Low-power_broadcasting> AM
<http://en.wikipedia.org/wiki/Amplitude_modulation> radio transmission
that uses the AC electrical system
<http://en.wikipedia.org/wiki/Mains_electricity> of a building to
propagate a medium frequency
<http://en.wikipedia.org/wiki/Medium_frequency> AM signal to a
relatively small area, such as a building or a group of buildings. In
the United States <http://en.wikipedia.org/wiki/United_States>,
carrier current stations do not require a broadcasting
<http://en.wikipedia.org/wiki/Broadcasting> license from the FCC
<http://en.wikipedia.org/wiki/Federal_Communications_Commission>, as
long as the emissions adhere to the Part 15
<http://en.wikipedia.org/wiki/Part_15> Rules for unlicensed transmissions.
Source:
http://en.wikipedia.org/wiki/Carrier_current
In Germany, carrier current transmission was called Drahtfunk
<http://en.wikipedia.org/w/index.php?title=Drahtfunk&action=edit&redlink=1>.
In Switzerland, Telefonrundspruch
<http://en.wikipedia.org/w/index.php?title=Telefonrundspruch&action=edit&redlink=1>
used telephone lines. In the Soviet Union
<http://en.wikipedia.org/wiki/Soviet_Union>, PLC was very common for
broadcasting since the 1930s because of its low cost and
accessibility, and because it made reception of uncensored
over-the-air transmissions more difficult. In Norway the radiation of
PLC systems from powerlines was sometimes used for radio supply. These
facilities were called Linjesender
<http://en.wikipedia.org/wiki/Linjesender>.
This was the forerunner of modern Internet censorship (30s style), but
let us continue for now...
In all cases the radio programme was fed by special transformers into
the lines. To prevent uncontrolled propagation, filters for the
carrier frequencies of the PLC systems were installed in substations
and at line branches.
An example of the programs formerly carried by "wire broadcasting" in
Switzerland:
* 175 kHz Swiss Radio International
<http://en.wikipedia.org/wiki/Swiss_Radio_International>
* 208 kHz RSR1 "la première" (French)
* 241 kHz "classical music"
* 274 kHz RSI
<http://en.wikipedia.org/wiki/Radiotelevisione_svizzera_di_lingua_italiana>1
"rete UNO" (Italian)
* 307 kHz DRS 1 <http://en.wikipedia.org/wiki/DRS_1> (German)
* 340 kHz "easy music"
When I will be retired O:-) , I will write a book about "Drahtfunk", and
how this old technology nearly was re-used for some ISO/MPEG "to be
defined" standard for active loudspeakers. And how this technoloGy
finally didn't make it , cos they couldn't find enough patents to
guarantee the future salaries of MPEG LA employees. And also because the
ITU didn't like all the provoked LF electro smog, caused by serious
music listeners.
And yet further: somewhere on the Web used to be details of using a wok
(as in cuisine) _basket_ (for ?deep fat frying?) as a reflector
('parabole') for WiFi ... was reputed to _greatly_ enhance range ...
(don't think it was a joke ...)
Joke? Are you kidding?! This was a bloody serious attempt to make WiFi
actually work...
Best,
Stefan
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