"The Ultra Low Frequency (ULF) is the frequency range between 300 hertz and 3 kilohertz. Many types of waves in the ULF frequency band can be observed in the magnetosphere and on the ground. These waves represent important physical processes in the near-Earth plasma environment. The speed of the ULF waves is often associated with the Alfven velocity that depends on the ambient magnetic field and plasma mass density. [NP] This band is used for communications in mines, as it can penetrate the earth. [1] [....] ULF has been used by the military for secure communications through the ground. NATO AGARD publications from the 1960s detailed many such systems, although one suspects the contents of the published papers left a lot unsaid about what actually was developed secretly for defense purposes. [....]"
[Based on: http://en.wikipedia.org/wiki/Ultra_low_frequency] - [T.D. 03/01/09]
Voice frequency
*Trivia: "A voice frequency (VF) or voice band is one of the frequencies, within part of the audio range, that is used for the transmission of speech. [NP] In telephony, the usable voice frequency band ranges from approximately 300 Hz to 3400 Hz. It is for this reason that the ultra low frequency band of the electromagnetic spectrum between 300 and 3000 Hz is also referred to as voice frequency (despite the fact that this is electromagnetic energy, not acoustic energy). The bandwidth allocated for a single voice-frequency transmission channel is usually 4 kHz, including guard bands, allowing a sampling rate of 8 kHz to be used as the basis of the pulse code modulation system used for the digital PSTN. [....] The voiced speech of a typical adult male will have a fundamental frequency of from 85 to 155 Hz, and that of a typical adult female from 165 to 255 Hz[1][2]. Thus, the fundamental frequency of most speech falls below the bottom of the "voice frequency" band as defined above. However, enough of the harmonic series will be present for the missing fundamental to create the impression of hearing the fundamental tone. [....]"
[Based on: http://en.wikipedia.org/wiki/Voice_frequency] - [T.D. 03/01/09]
Alfvén wave
*Trivia: "An Alfvén wave in a plasma is a low-frequency traveling oscillation of the ions and the magnetic field (by low frequency we mean that the wave frequency is well below the ion cyclotron frequency). The ion mass density provides the inertia and the magnetic field line tension provides the restoring force. [NP] The wave propagates in the direction of the magnetic field, although waves exist at oblique incidence and smoothly change into the magnetosonic wave when the propagation is perpendicular to the magnetic field. [NP] The motion of the ions and the perturbation of the magnetic field are in the same direction and transverse to the direction of propagation. The wave is dispersionless. [....] How this phenomenon became understood: 1942: Alfvén suggests the existence of electromagnetic-hydromagnetic waves in a paper published in Nature. 1949: Laboratory experiments by S. Lundquist produce such waves in magnetized mercury, with a velocity that approximated Alfvén's formula. 1949: Enrico Fermi uses Alfvén waves in his theory of cosmic rays. According to Alex Dessler in a 1970 Science journal article, Fermi had heard a lecture at the University of Chicago, Fermi nodded his head exclaiming 'of course' and the next day, the physics world said 'of course'. 1950: Alfvén publishes the first edition of his book, Cosmical Electrodynamics, detailing hydromagnetic waves, and discussing their application to both laboratory and space plasmas. 1952: Additional confirmation appears in experiments by Winston Bostick and Morton Levine with ionized helium 1954: Bo Lehnert produces Alfvén waves in liquid sodium 1958: Eugene Parker suggests hydromagnetic waves in the interstellar medium 1958: Berthold, Harris, and Hope detect Alfvén waves in the ionosphere after the Argus nuclear test, generated by the explosion, and traveling at speeds predicted by Alfvén formula. 1958: Eugene Parker suggests hydromagnetic waves in the Solar corona extending into the Solar wind. 1959: D. F. Jephcott produces Alfvén waves in a gas discharge 1960: Coleman, et al, report the measurement of Alfvén waves by the magnetometer aboard the Pioneer and Explorer satellites 1960: Sugiura suggests evidence of hydromagnetic waves in the Earth's magnetic field 1966: R.O.Motz generates and observes Alfven waves in mercury 1970 Hannes Alfvén wins the 1970 Nobel Prize in physics for 'fundamental work and discoveries in magneto-hydrodynamics with fruitful applications in different parts of plasma physics' 1973: Eugene Parker suggests hydromagnetic waves in the intergalactic medium 1974: Hollweg suggests the existence of hydromagnetic waves in interplanetary space 1974: Ip and Mendis suggests the existence of hydromagnetic waves in the coma of Comet Kohoutek. 2007: Tomczyk, et al, report the detection of Alfvén waves in images of the solar corona with the Coronal Multi-Channel Polarimeter (CoMP) instrument at the National Solar Observatory, New Mexico. 2007: Alfvén wave discoveries appear in articles by Jonathan Cirtain and colleagues, Takenori J. Okamoto and colleagues, and Bart De Pontieu and colleagues. De Pontieu’s team also shows that the energy associated with the waves is sufficient to heat the corona and accelerate the solar wind. These results appear in a special collection of 10 articles, by scientists in Japan, Europe and the United States, in the 7 December issue of the journal Science."
[Based on: http://en.wikipedia.org/wiki/Alfven_velocity] - [T.D. - 03/01/09]
Ultra-Low Frequency (ULF) Wave Study
http://www.darpa.mil/sto/strategic/ulf.html
Electromagnetic Weapons and Mind Control
http://www.mindcontrolforums.com/cnn-mc.htm
Symbol definitions: * NP = New paragraph (A paragraph break symbol used to save space when transcribing material.) *T.D. = Transcription date (Date material transcribed to this page and date of quoted page.) - D.R.D.
Last page update: 03/01/09
