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Power Grid Radio Telescope

The North American Power Grid is the Largest Radio Receiver Ever Built
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Power Grid Radio Telescope

The North American Power Grid is the Largest Radio Receiver Ever Built

Yes friends, the biggest and probably most sensitive radio receiver that costs nothing to build - because it already exists!

A vast array of wires and cables totalling billions of kilometers in length, stretched out over vast areas of the Earth's surface.

Signals can be digitized at many points simultaneously. These signals are then analyzed via Fast Fourier Transform and other time/frequency domain methods. With a large enough set of sampling stations, noise and non-useful signals can easily be filtered out, leaving what we want.

If filtering proves infeasible, the entire grid can be shut down some night using nonlegal methods. This will provide a few precious minutes/hours to listen to the cosmos with a higher sensitivity than ever imagined.

The entire grid is interconnected though (mostly) magnetic transformers. These pass signals of wide enough frequency range. For example, currently a system is being examined by the FCC called "Broadband over Powerlines" or BPL. It uses certain frequencies to transmit TCP/IP packets over power lines.

From a docket submitted to the FCC by the National Academy of Sciences Committee on Radio Frequencies:

p.3: "While radio astronomers make observations at many frequencies that could be affected by emissions from BPL systems, CORF is particularly concerned about the following frequencies..."

13.36-13.41 MHz 25.5-25.67 MHz 37.50-38.0 MHz 38.0-38.25 MHz 73.0-74.60 MHz 406.1-410.0 MHz 608-614 MHz

Location: http:// www7.nationalacademies.org / corf / CORF_5_3_04_Filing_2.pdf # search=%22 powerline%20 radiotelescope%22

If the NAS is concerned about interference, it is obvious that powerlines can carry such frequencies over long distances, evidenced by existing BPL systems' usage of them. However, the BPL sytems they mention may be home-use (short distance).

For Access Broadband over Powerlines (ABoP), some useful information:

http:// en.wikipedia.org /wiki / Power_line_communication

In particular, the frequency range of 20-350 KHz is what interests us. It may be narrow from an astrological viewpoint, but the sensitivity and scope is enormous. Later in the same Wikipedia entry, the range 1.6-30 MHz is mentioned for the carrier.

Isochroma, Aug 29 2006

(??) Maybe not such a good site to visit. My computer didn't think so - mentioning Malicious & such. http:// www7.nation...0 radiotelescope%22
(You can copy the address & paste it into link using the link button) [Zimmy, Aug 29 2006]


       Welcome to the halfbakery, iso. You can link by clicking on [link] directly under your idea, so readers don't have to cut and paste. BTW, your posted idea should be yours, and not something repeated from the web.
ldischler, Aug 29 2006

       This has been proposed before. There are a large number of problems, but most of them boil down to signal/noise.   

       The power grid is designed to do one thing. Deliver power at approximately 60Hz and a variety of voltages. It can be pretty darn sloppy in how it does this, especially on the large long distance lines. Any power from these lines is going to be stepped down and effectivly filtered before delivery. The grid was constructed piecemeal over decades with little internal consistancy, as that is not needed for the purpose.   

       Radio telescopes need to be quite precise and consistant. They are trying to pull slight variations out of a rather loud background. Components need to be consistant and provide reliable repeatable results.   

       Using the power grid as a giant antenna might allow an astronomer to pick up very faint signals, but they would be impossible to pull out of the noise generated by the equipment.   

       If you want to see a very interesting giant radio antenna project, google "Primeval Structure Telescope" for a scope constructed in Mongolia of 100,000 television antennas.
Galbinus_Caeli, Aug 29 2006


       I didn't know about the link option - still can't find it. And this is an original idea, and I spent lots of time searching and couldn't fine any references to it. I dreamed it up one night about 4 years ago while listening to elecronic music after a joint :)   

       The links in my article are supporting evidence only.
Isochroma, Aug 29 2006


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