THE WORLD’S LARGEST
“RADIO” STATION
by CARLOS A. ALTGELT
FIRST MADE PUBLIC by the US Navy in 1968 as Project Sanguine (1),
the Extremely Low Frequency communications project—Project ELF—is
designed to communicate with deeply-submerged submarines. Project ELF
uses low-frequency waves to signal one-way coded messages to US and
British Trident and Fast Attack submarines. The system alerts them to
surface to receive a more detailed communication.
Mammoth Projects...
Project Sanguine would have made use of some two-fifths of Wisconsin in
the construction of a giant ELF transmitter capable of being heard all over
the world. A committee set up to investigate possible biological effects
vetoed the
concept. A new variant, Project Seafarer, was next proposed. Again, the
system was halted. Finally, Project ELF was approved and can now
broadcast at frequencies between 30 Hz to 300 Hz.
Project ELF, which became operational in 1989, consists of two
transmitters, one near Clam Lake in Northern Wisconsin, and the other at
Republic, in Michigan’s Upper Peninsula. (Actually, Michigan’s antenna
intersection is located east of Republic, while the transmitter site is in the
Gwinn area nearby, with no settlements of any size between the two
towns.)
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The Michigan and Wisconsin sites, separated by 145 miles as the crow
flies, must operate simultaneously to meet worldwide coverage
requirements.
...with Huge Antennas
One of the great difficulties associated with the use of ELF for
communication purposes, is the problem of generating a useful signal. The
physical size of an antenna that can produce a useable signal with
reasonable efficiency is inversely proportional to the frequency.
The Wisconsin antenna consists of two lines, each about 14 miles long.
The Michigan antenna uses three lines, two about 14 miles long and one
roughly 28 miles long.
Originally, the antennas were to be buried 6 feet underground, but
reasons of economy dictated otherwise. The antennas that were actually
built look like a power line, mounted on 40-foot wooden poles with a
transmitter building near each antenna system. The transmitter facility in
Michigan uses about six acres of land and the one in Wisconsin, deep in the
Chequamegon National Forest, about two acres. A 165-mile underground
cable connects the two sites which have a typical operating frequency of 76
Hz. Due to its low frequency, the antenna systems is huge: a directlygenerated
electromagnetic wave at 76 Hz has a wavelength of 2,452 miles.
The very first ELF transmission from Clam Lake (an old Navy facility
built years before Michigan’s site) took place in May 1982, when a
message was successfully received by a submarine submerged at a depth of
400 feet in the Atlantic Ocean off the Florida coast. According to Paul
Brodeur (Currents of Death), that experiment so impressed a newspaper
publisher that he promptly endorsed Project ELF.
The submarine detects a Nevada-site ELF signal with a long trailing antenna
that stretches for several hundred yards behind and above its deck.
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Underwater Signals
As a result of the high electrical conductivity of sea water, signals are
attenuated rapidly as they propagate downward through it. In effect, sea
water "hides" the submarine from detection while simultaneously
preventing it from communicating with the outside world through
conventional high-frequency radio transmissions. In order to receive these,
a submarine must travel at slow speed and be near the surface.
Unfortunately, both of these situations make a submarine more
susceptible to enemy detection. Lower frequencies, such as those in the
ELF range, however, can be received considerably deeper in the ocean.
Project ELF’s signal of 76 Hz is capable of forming strong wavefronts
and penetrate well below the ocean’s surface. (Very Low frequency (VLF)
signals, those between 3 kHz to 30 kHz were used by the Navy before but
they can barely penetrate the water’s surface—see sidebar above.)
Millions of watts are transformed into a 2,500-mile long wave that
A Greek…
Navy officials had become interested in ELF radiation back in
1958, when they learned that radio waves oscillating just above
the 60 Hz range could penetrate seawater sufficiently to provide
communication with deeply submerged submarines. Because the
wavelength of such a signal is nearly 2,500 miles, it was feared at
the time that ELF transmitting antennas would have to be unduly
large. This problem was solved, however, by Nicholas
Christofilos, a brilliant Greek-born physicist working for the
Department of Defense, who suggested that a portion of the
earth’s interior could be used as a launching pad to propagate
ELF signals. During the early 1960s, Christofilos’s concept was
successfully tested, and in 1969 the Navy and the RCA
Corporation built an ELF test facility near Clam Lake, Wisconsin,
by burying twenty-eight miles of insulated cable in the lowconductivity
granite bedrock of the Chequamegon National Forest.
Soon thereafter, the Navy proposed to construct a 22,500-
square-mile antenna system [by] burying 6,000 miles of cable in
bedrock elsewhere in Northern Wisconsin and in the Upper
Peninsula of Michigan. The idea was to form a giant grid so that
electric current generated by transmitters would pass through the
antenna cables and flow deep into the earth along the bedrock,
creating a global ELF radio field [NB: it would certainly be an
electromagnetic wave, but definitely not a “radio” wave!] extending
up to the ionosphere [which] would reflect a portion of the ELF
field into the world’s seas and oceans.
Paul Brodeur (Currents of Death)
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turns the Laurentian granite bedrock of Lake Superior into a massive
antenna for deep sea contact with the submarine fleet. The efficiency of
these transmitters is very poor, however, and a large amount of energy is
wasted as heat.
Technical Data
An ELF message provides
basic information. It’s
really a backup of existing,
higher-frequency, radiobased
communication
systems. But, while ELF
signals do not provide the
rate of information and
speed of transmission of
other systems, it “gets
through” while the others
cannot. As we pointed out
in the previous page, it is
also a one-way, non-voice system, but it provides sufficient information to
the submarine’s commander to surface to receive more information via
other means.
Overhead Antennas
The ELF antennas,
resembling an ordinary power
distribution line, are located
above ground in cleared rightof-
ways that are 70-100 feet
wide. The antennas consists
of two conductors in
Wisconsin and a single
conductor in Michigan. The
transmitter sends an electrical
current through the antenna
cables into the earth at the
ground terminals. The end of
each antenna element is
terminated with one to three
miles of buried horizontal
ground wire and typically one
or more arrays of well-type
electrodes extending to
depths of 100 to 300 feet.
The current then flows back
to the transmitter through the
earth, completing the circuit.
Most of the earth current flows deeply, and disperses through the non-conductive
bedrock underlying the ELF system around and between the two sites.
(From IIT Research Institute reports.)
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Once on the surface, the commander will receive the detailed orders via
more conventional VLF signals at 17 kHz and 26 kHz. Most of the
communications are done by raising a mast out of the water and querying a
submarine.
A problem with the signal is the inefficiency of the antenna system: it
takes a long time to send a very short message via ELF. While a radio signal
can carry vast amounts of information, ELF is very slow. Based on
parameters supplied by the Navy, estimates have ranged from 1 bit per
second to 1 bit per 10,000 seconds. But the Navy feels that low data rates
present no problems, since signals of just a few letters can convey quite a bit
ELF MODULATED WAVEFORM AND POWER SPECTRAL DISTRIBUTION
The US Navy ELF Communications System uses a frequency modulation
principle known as “minimum key-shifting” centered around 76 Hz. In this
type of modulation, the signal consists of smoothly connected segments of
sinusoids of two distinct frequencies. The figure shows a signal shifting
between 72 Hz and 80 Hz depending on whether an analogous code of
“one” or “zero” is being transmitted. Transitions from one frequency to the
other occur at the peak of zero crossings of a wave in order to minimize the
bandwidth of the frequency spectra. Both transmitters at Clam Lake and
Republic can operate at other center and shift frequencies but have not
done so operationally. These 76 HZ FM signals have field intensities much
larger (and mask) ambient 60 Hz unmodulated field intensities generated by
power utility transmission and distribution lines.
(From Technical Reports D06205-3 and D06214-6
by the IIT Research Institute, Chicago.)
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of pre-encoded information (no pun intended!). A Navy spokesman claimed
that the Navy is “in a way . . . going back to the days of flag hoists . . .
when we had the general signal books and ran whole fleets for whole wars
on just two- and three-letter signals” (US Navy’s Seafarer Final
Environmental Impact Statement, April 1972). But, in the same report, a
congressman suggested that only a few characters could be sent every 15
minutes while others estimated that it will take almost two hours to send a
coded message just twelve letters long.
Geological Requirements
An ELF antenna sends a signal from the ground to the ionosphere where it
travels around the world filtering down through the ocean depths to reach
the fleet of submarines (see figure above). Due to the limits of the lengths
of the system’s antennas (less than 100 miles versus the required 2,500
miles to generate a 76 Hz electromagnetic wave), the antennas are placed
near nonconductive rocks from the Precambrian era. To be useful, the
rock formation must be fairly close to the surface and be large enough to
support the ELF antenna grid. The rocks must be as nonconductive as
possible so as not to “shorten” the electromagnetic wave.
Few places in the United States meet those conditions, Wisconsin and
Michigan being the best two.
Power-A-Plenty
At the outset, Project Sanguine was to require 240 transmitters and a total
power requirement of 800 megawatts with a current of 100 amps. The
total land area needed was estimated at 20,000 square miles (about the size
…and a German
ELF was accidentally detected in World War I when the Germans
noticed a very low frequency noise in the ground which had a
strong resonance at 7 Hz [The] Germans felt that the noise was
caused by electrical storms. The phenomenon was dismissed as
interesting but of no practical use. It was not until the early 1950s
that interest in ELF began again. In 1952 a German scientist
named W. O. Schuman pointed out the existence of a cavity
between the earth and the ionosphere that has a fundamental
resonant frequency of about 7 Hz. A radio wave having the same
frequency [NB: one more time, it isn’t a “radio” field!] can be
broadcast into this cavity [and] will travel 25,000 miles around the
world at the speed of light. [Other] scientists quickly added to
Schuman’s discoveries. They found out more about the
resonances: frequencies below 100 Hz do not fade out. [These]
discoveries set the stage for the ELF concept.
L. W. Klessig and V. L. Strite (The ELF Odyssey)
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of Belgium and Holland combined). In the end, the power required for the
Michigan and Wisconsin sites was reduced to less than 5 megawatts and
eight acres for the transmitter sites.
According to Lowell L. Klessing and Victor L. Strite, “The reduction
in land area and power required was made possible mainly because of a
scientific breakthrough reported in November 1969. The nature of the
breakthrough was never made clear. The discovery allowed smaller
transmitters and 90% lower space requirements. Other technological
advances then and later allowed for a compensating decrease in power:
improved lightning neutralization, improved radio direction finder on
submarines, increased knowledge about site conductivity, and improved
antenna and receiver techniques. All of these improvements reduced the
power requirements by a factor of 100, the Navy claimed.” (2)
ELFS IN THE FOREST
Each facility consists of a transmitter, pole-mounted antenna cables, and
buried ground terminals where the antenna currents enter the earth. The
Navy Radio Transmitting Facility (NRTF) transmitters are located near the
intersection of the antennas in each site. The NRTF at Clam Lake has
two orthogonal antennas, one essentially oriented north-south (NS) and
ther other east-west (EW), resembling a large “X.” Each antenna is 14
miles long and carry 300 amperes. The NRTF at Republic has one NS
antenna (28 miles) and two parallel EW antennas (14 miles each), the
whole system resembling an enormous “F”; overall current is 150
amperes. The transmitters have been operated either synchronously or
independently to broadcast messages.
(From Technical Reports D06205-3 and D06214-6 by the IIT Research Institute, Chicago.)
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Not in My Backyard
ELF transmitters have been the object of protests since their inception 30
years ago. In June 1998, US Senators Russ Feingold and Herb Kohl
introduced an amendment to the Defense Authorization Bill which would
terminate Project ELF. “Project ELF is an ineffective, unnecessary, and
outdated Cold War relic that is not wanted by most residents in my state,”
said Feingold. “We have almost succeeded in terminating the project
twice before, and we are going to keep at it until we do. There is no doubt
in my mind that the millions of defense dollars we spend on ELF can be put
to better use supporting the National Guard.” Ten editorials have appeared
in Wisconsin and Michigan newspapers calling for ELF to close.
In 1996, one protester, Tom Howard-Hastings went into “the world’s
largest radio station,” as he misnamed the Michigan’s site (after all, it sends
no “radio” waves as such) and cut down three of the antenna poles,
shutting down the system for a couple of days.
Wisconsin and Michigan residents object to the ELF transmitters too,
calling the project a nuisance. Metal fences in the surrounding area, for
example, must be grounded to avoid severe shocks from the presence of
high voltages. Several
NRTF-Republic, Michigan
After the Clam Lake NRTF transmitter in Wisconsin was completed,
construction of a second transmitter near Republic, Michigan, started in
1983. Intermittent operation began in March 1986 with low power
testing, becoming a fully-operational Naval Communications Facility in
October 1989. Since that time, it has operated at full power essentially
24 hours per day.
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THE GOLDEN FLEECE AWARD
More than 20 years ago, former Senator William Proxmire created the
"Golden Fleece Award" to focus public
attention on budgetary waste in government in
the form of pork-barrel spending. He issued a
Golden Fleece Award every month between
March 1975 and December 1988. In his own
words, the award singled out a "wasteful,
ridiculous or ironic use of the taxpayers'
money.”
The dubious distinction of a Golden Fleece
Award was granted to federal programs that
most Americans would agree were outrageous
and wasteful. The Golden Fleece Awards did not necessarily have high
costs, but rather violated a principle of responsible government spending.
For example, in December 1981, he bestowed a Golden Fleece award
on the US Navy for keeping a bull at their Clam Lake Project ELF facility in
Wisconsin as part of the Navy’s ELF health effects research program.
Over the years, almost every federal agency has received a Golden
Fleece Award.
residents claim to hear the "Taos Hum,” a low, grumbling noise on the
threshold of audibility. The hum is so named because it first received
massive publicity in 1990 when it became "loud" in the New Mexico area
around Taos. Soon many other people started reporting that they also
could hear the “Taos Hum" worldwide.
On the other hand, faculty and researchers at the Michigan
Technological University (MTU) School of Forestry and Wood Products
have found that the Project ELF’s antenna grid makes the trees grow faster.
MTU foresters have been studying the effects ever since the system became
operational ten years ago. •
Note: Drawings from the book The ELF Odissey by L. Klessig and V. Strite.
(1) The project was in secret research and development in North Carolina and
Virginia during 1958-67.
(2) The ELF Odyssey: National Security Versus Environmental Protection,
Westview Press, 1980.
