Can you identify this mystery sound?
Something different now, but perhaps familiar.
Today we have a small challenge, a mystery sound to identify. Listen to
it carefully and see if you can identify it.
Click
here to hear the sound
Now, click here to see if you were right.
Earlier we played our "mystery sound".
Could you can identify it?
The mystery sound is a recording of tuning across just 8KHz of the 40m
band on a recent Sunday afternoon in Queanbeyan in south eastern NSW where
there is a BPL trial underway.
Let's hear it
again.
You might ask why did I select that 8KHz segment? No reason at all,
the entire band was affected in the same way.
What you heard was entirely BPL interference, a series of carriers spaced
approximately 1.1KHz, and equivalent in strength to 30dB over S9 on the
S meter of an amateur station with a dipole 15metres from the powerlines.
Under data traffic the sound changes, the carrier power is
redistributed to broad raspy noise, but still at the same signal strength.
You can read a report on my observations of the trial on 21 November on
my website, go to www.vk1od.net/bpl,
there are prominent links to the report and other relevant BPL information
and tools.
And while we are measuring and reporting radio interference at unprecedented
levels, the BPL industry is hailing the success of their trials. Let me
quote to you from Tasmania's Aurora Energy's 2004 Annual Report under
the headline "Powerline communications pilot".
"A major Tasmanian ' commercial trial of powerline communications
(PLC) technology is due to begin towards the end of the 2004/2005 financial
year. This follows the successful proof of concept pilot conducted by
Aurora earlier this year in partnership with Japan's Mitsubishi Electric
and Tasmanian company, KeyPoint Internet. The pilot delivered broadband
internet and voice services over low-voltage powerlines to Aurora's head
office in Hobart as well as four adjacent private businesses in Kirksway
Place. It was watched with interest by utilities from around Australia
including Energy Australia, Country Energy, Transgrid, Hydro Tasmania
and the Australian Communications Authority (ACA)."
In a world where the constant is change, the question for each of us is
whether we will passively accept the outcome, or whether we want to influence
the outcome.
There are opportunities for individual projects, or radio club led projects
in this pursuit, but we need to speak with one voice.
Now, more than ever before, we need to be effectively represented to government
and industry. Our lobbyist is the national WIA, and it depends on your
direct membership for its authority.
Owen Duffy
BPL, it may be coming to a power point near you sooner than you think.
National WIA news keeping you up to date with current
news of Broadband over Power Lines in Australia.
Source: Wireless
Institute of Australia
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