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Here's a site that has good info about using your sound card as an ELF receiver - you hook an antenna right to the mic input since the 'RF' involved uses the same frequencies as we humans hear (and are generated by microphones, etc).

http://www.vlf.it/ - all sorts of ways to receive ELF/VLF with a soundcard.

Your ears may not be able to detect these, but your computer's soundcard can. It can also detect all sorts of other ELF transmissions. Check out http://www.vlf.it/ - fascinating stuff!

Your ears may not be able to detect these, but your computer's soundcard can. It can also detect all sorts of other ELF transmissions. Check out http://www.vlf.it/ - fascinating stuff!

The Russians still use a hell of a lot of HF. For the Russians it is tried and tested and an essential back-up for use in an EMP environment and especially with Morse Code. Their Morse networks are still very active.

UVB-76 uses the same format for its flash priority codeword message as do the other Russian Military Networks.

The clue is in the Russian Navy set up. Using fixed callsigns these have been easily identifiable for decades. Note the format of the Flash Message which is exactly the
same as the flash codeword pattern on UVB-76.

http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/aboutmorsenetworks/index.html

http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/index.html

The Russian Navy still use Morse to control their fleet of Naval Transport Aircraft.

http://www.astrosol.ch/networksofthecisforces/navymorsenetworks/navalairtransportunits/index.html

From

http://www.astrosol.ch/index.html

This flash codeword traffic is also noted on the Russian ELF and VLF networks

http://www.vlf.it/zevs/zevs.htm

See examples of codeword traffic intercepted on Russian Military networks by radio enthusiasts. Note the frequency range.

http://www.cvni.net/radio/nsnl/nsnl131/nsnl131mil.html

Methinks that antenna looks like the fabled Octoloop (look about 3/4 down the page). Granted, it provides some useful antenna gain, but another disadvantage (in addition to its' large size), is that it has a very narrow beamwidth. This would restrict reception on the surface to a very specific location which would be hard to determine in a rescue situation if the rescueres don't know where the transmitter is located.

None-the-less, there is probably some niche applications for this (fault monitoring?) and I wish the inventor student the best of luck.

Developed by Los Alamos National Laboratory, the Through-The-Earth Communication system proved capable of sending two-way, very-low-frequency (VLF) voice signals from the surface of the mine to depths exceeding 300 feet at the experimental mine operated by the National Institute for Occupational Safety and Health (NIOSH).

The Through-The-Earth Communication system was developed for the U.S. Department of Energy at Los Alamos National Laboratory's Superconductivity Technology Center with a development team led by David Reagor. The technology has also earned a prestigious R&D 100 Award from R&D magazine.

The system uses VLF electromagnetic radiation in the range of 3 to 30 kilohertz (kHz) and digital audio compression to transmit wireless voice and data signals through the earth. Materials that block higher radio frequency (RF) signals, such as rock, concrete, metal, and high-density ore bodies, do not restrict its signal

Incorporating Sprint/Nextel i325 mobile phones, supported by Raytheon's JPS Communications ACU 1000 cross-band repeaters, the Through-The-Earth Communication system demonstrated its capabilities in the Lake Lynn Mine, which is composed of several long tunnels used for mine safety experiments. The mine consists of nonflammable limestone with a tunnel height of about 10 feet and an overburden of up to 370 feet. Test Of Through-The-Earth Communication System Exceeds Expectations [August 2007]

VLF appeals to radio hobbyists because of its exotic associations with both natural science and submarine warfare. To get started all you really need is a PC and a home-made antenna. Radio Waves Below 22 Hz

http://www.vlf.it/alphatrond/alpha.htm

If you want to see how these Alpha signal look like, take a peak at this Web Softwarre Defined Radio located in the Netherlands, operating in the VLF band. It is picking up 2 of the 3 stations (Krasnodar and Novosibirsk). They look like long Morse dashes around 11 to 15 kHz frequencies.

http://websdr.pa3weg.nl/

Johanus

See this excellent VLF/ELF site for more info regarding the world below 100kHz.

The earth has an electromagnetic field resonance. Investigate it and other VLF/ELF phenomena further here.

Get a program called SPECLAB, hook up a few hundred meters of coiled cable and plug it into the mic socket. Now witness the 15KHz tone of TV's in a lush waterfall pattern. It's a bit like the matrix, I can tell when a train goes past on the line a few hundred meters from my house, when someones using a drill in my street etc etc.

See here for more info: http://www.vlf.it./ Check out their Unexplained signals gallery, much fun. Just watch out for those russian ZEVS transmissions, I could go on for hours about it so.....

Cheers!

A quick Google search revealed the following: ZEVS, THE RUSSIAN 82 Hz ELF TRANSMITTER. Located near Murmansk. The article has some nice maps, screenshot of the spectrum, etc.

Remember, due to the fact that Russia still has and uses en ELF transmitter , everybody is still exposed to ELF radio waves. But as you said, people have a "negative NIMBY" effect when something they perceive as useful is involved.

In this cases, I have a good Litmus test before getting involved in a discussion:" If an emitter is dangerous at a distance of 1 meter, how much will it be harmful at 2 meters?"

Guess what: most people say:"Half"

The Navy has used 76 Hz to communicate with submarines 300-400 ft down. Stations, ITU Licences and Services Below 22 KHz.

You're probably referring to the Schumann resonance, the resonance of the earth-ionosphere resonant cavity. Energy from lightning around the world excites this resonance, which then rings--much as hitting a bell with a hammer causes the bell to ring.

Also like an acoustic bell, there is a fundamental frequency of resonance and many overtones that grow fainter as you go up in frequency. The fundamental Schumann resonance is approximately 7.8 Hz; the first few overtones are usually given as 13.8, 19.7, 25.7, and 31.7 Hz. There is a slight variation in the frequencies involved over long periods of time, as the ionosphere changes in response to solar activity.

Even better, muck around with VLF/ELF radio. You can hear much more interesting stuff than just the sky, like whistlers from thunderstorms for starters...

Check out vlf.it for some interesting stuff on VLF/ELF radio.