Although hyperbolic systems as such, were never pursued to
completion in Germany, Dr. Ernst Kramar, working at Standard Elektrik Lorenz
in 1938, developed an improved version of the American Radio Range which
was able to provide multiple fixed equisignals for defining multiple routes
(Elektra). After German military use early in W.W. II, Dr Kramer was asked
whether he could improve it to provide directional information between
the equisignals. He did so, and it was re-named Sonne, after a character
from the operas. Consol is actually the name the British assigned to the
system.
There were also to have been other versions known as Mond (Moon) and
Stern (Star) operating at other frequencies. Dr. Kramar has related how,
being a devotee of Richard Strauss's music (hence Elektra), he wished to
name it Salome but was overruled by the Luftwaffe. This system was installed
in Norway, France and Spain as a navaid for German aircraft flying the
circuitous route over the Atlantic between France and Norway, and their
U-boats. It is an example of a 'collapsed' hyperbolic system wherein the
baseline between the transmitting aerials is made so short that the hyperbolae
degenerate into radials at a very short distance and the system becomes
a bearing system rather than a hyperbolic one.
Sonne/Consol used three aerials spaced on a line 1.5 miles long, or
about three wavelengths at the operating frequency of 300 kHz. An identical
signal was fed to all three aerials but at one outer aerial, it was delayed
by 90 degrees of phase while at the other outer aerial it is advanced by
90 degrees. Multiple lobes with deep nulls between them were produced by
the interaction of the three aerials. By steadily changing the phase shift
in the two outer aerials so that it interchanged every 30 seconds, these
lobes were caused to sweep. They were also switched at a very much faster
rate in synchronism with a Morse pattern of dots and dashes, the effect
being that each lobe carried only either dots or dashes and was replaced
by its complement over the 30 second period.
The navigator only needed an ordinary radio receiver tunable to
300 kHz in order to use the system.. He heard a series of dots slowly merging
into a steady tone and then becoming a series of dashes (or -dashes becoming
dots). He simply had to count how many dots or dashes he could hear before
the steady tone and then plot his position line on a suitably overprinted
map. There were multiple ambiguities in the system since there was no inherent
way of distinguishing between one lobe and another. At its narrowest each
lobe, it was only about 7.5 degrees wide. They were resolved either by
approximate knowledge of position or by taking a loop bearing on the station.
For this purpose, a steady tone was transmitted for a few seconds before
each sweep, from the central aerial only. One station did not provide a
fix, of course, but it was a very useful system requiring little expertise
to use and only simple equipment.
Consol was one of the recommended ICAO navaids after WW II. Additional
transmitters were installed near New York, San Francisco, in the USSR,
and in the UK (Bush Mills in Northern Ireland). RAF navigators found the
system of considerable value, and it had the curious distinction of being
a wartime navaid used by both sides simultaneously. There is even a story
that at one time the Germans had problems with their Spanish transmitter
and could not get spares to it, so the British supplied the Spanish with
the necessary items in order to get the station back on the air for Coastal
Command's benefit.
Jose Ramon of Lugo Spain ( pop around 100,000) reports that he
lives about 25 km from the Consol aerials and the station that was
installed in 1941. It used Telefunken equipment and he thinks it was closed
around 1984. After closure, the station was abandoned and the equipment
was picked clean by those seeking parts but the antennas are still there.
The Lugo Consol station was located at 43º 14´ 53.29´´
N, 7º 28´55.89´´W.
Consol had a range of up to 1,000 - 1,200 miles and an accuracy of bearing
of around one- sixth of a degree (3 miles at 1,000 miles range). It used
the principle of "collapsed hyperbolic" for operation. Consol suffered
from all the usual propagational problems of these frequencies of night-time
skywave and static. Station LEC located at Stavenger Norway and operating
on 319 kHz, was the last Consol station to go off the air sometime after
1991.
Sven Pran, LA7SG, was the project manager for Consol at "Standard Telefon
og Kabelfabrik", a sister company to SEL. He adds the following " I had
the pleasure of meeting Dr. Ernst Kramar while we worked on the new
all-electronic construction for Consol. We first built three new stations
LEX at Andøya, LJS at Bjørnøya and LMC at Jan Mayen
in 1970 and then replaced the old LEC at Varhaug in 1971.
Since the lobe ambiguity is greater than 7.5 degrees, you are correct
in stating that the resolution is 6 counts (elements) to each degree (at
best), and as there is 30 "elements" in each lobe, every second lobe starting
with dots the other with dashes. The ambiguity to be resolved by other
means is at least a full 10 degrees.
Both the British and Germans used Sonne/Consol for navigation and that's
probably the reason the stations were never destroyed except, according
to Kramar, in one single case.
Kramar had found a way of modifying Consol so that it gave useful signals
only to the Germans but not to the British. That station, according to
what I was told, was bombed and subsequently rebuilt in its original configuration
and useful to both sides! However, I cannot confirm the story that the
English actually should have supplied spare parts to Lugo.
I visited Spain in June 1970 as a guest to the Spanish ministry dealing
with Consol. The purpose was to propose a replacement system for their
then worn out Consol stations in Lugo and Sevilla. As part of that trip,
I also visited the Sevilla station which then operated only as a non-directional
beacon for the main route to South America. I was told that Lugo
had already been completely closed down by then and I believe that Sevilla
closed down not long afterwards. Nothing came out of this visit. I found
it most unbelievable that either of the Spanish stations could have remained
operational for so many years after my visit".
In Russia, a Consul station call sign KN, was located around Cape Kanin
which is at the northern tip of Novaya Zemlya, It's frequency was
in the vicinity of 269 or 270 kHz. There was another one, call sign
RB, a bit higher in frequency located in the Far Eastern section
of Russian, around Provideniya.
REFERENCES:
1) The Journal Of Navigation - Chapter 4.
W.F. Blanchard, Royal Institute of
Navigation;
Vol 44, No. 3; Sept 1991. Used with
permission.
2) Admiralty Manual of Navigation. Her Majesty's Stationary
Office. 1955
3) Jose Ramón. E-mail: "jramon" <jrigel(at)terra.es>
or <jriazor(at)vodafone.es>
4) Sven Pran E-mail: svenpran(at)online.no
23 Jan 05
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