Naxos radar detector
Encyclopedia
The FuG 350 Naxos radar warning receiver
was a World War II
German countermeasure to SHF band
centimetric wavelength radar produced by a cavity magnetron
. It replaced Metox
, which was incapable of detecting centimetric radar.
Telefunken
built a simple detector named "Naxos" that could pick up 10 cm / 3 GHz
H2S radar
transmissions, and a more sophisticated detector named "Korfu" with greater range and accuracy.
Korfu saw little use, but Naxos saw widespread service. There were two different types of Naxos. "Naxos Z" was developed for night fighters and mounted in a teardrop-shaped blister on top of the fighter's canopy. It could detect an RAF bomber from much longer range than FuG 227 Flensburg
. Another version, the S-band (2500-3700 MHz, 12–9 cm wavelength) FuMB7 Naxos U, was provided to U-boats to allow them to detect 10 cm / 3 GHz ASV (air to surface vessel) radar, though by that time the U-boats were entirely on the defensive and it did them only a little good. By one of those weird coincidences which occur in wartime, the U-Boats received their Naxos 10 cm detectors on the same day that RAF Coastal Command deployed its first 3 cm ASV radar sets. Naxos was further hobbled by the fact that it proved very fragile in field conditions, and working out the bugs ended up being a difficult task.
The "Naxos ZR" was fitted to the tails of German night fighters to warn them if they were being tracked by RAF De Havilland
Mosquito
night intruders fitted with the AI Mk.IV radar and its derivatives.
Naxos receivers were also combined with the parabolic antennas from Würzburg radar
systems to produce a long-range receiver tuned to the British Oboe
radio navigation
system. The system later used a Domeyer receiver and became the Naxburg system. Oboe broadcast pulses from the aircraft that needed to be powerful enough to be received by ground stations in the UK. This made them relatively easy to pick out at short ranges, as long as the receiver was tuned to a suitable frequency. When such a signal was detected, false pulses identical to those received from the aircraft were re-broadcast from the ground. Stations in the UK thus received two or more signals for every signal they sent out, which confused the detectors. The British had used a similar system against the German navigation systems earlier in the war.
Radar warning receiver
Radar warning receiver systems detect the radio emissions of radar systems. Their primary purpose is to issue a warning when a radar signal that might be a threat is detected. The warning can then be used, manually or automatically, to evade the detected threat...
was a World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
German countermeasure to SHF band
Super high frequency
Super high frequency refers to radio frequencies in the range of 3 GHz and 30 GHz. This band of frequencies is also known as the centimetre band or centimetre wave as the wavelengths range from ten to one centimetres....
centimetric wavelength radar produced by a cavity magnetron
Cavity magnetron
The cavity magnetron is a high-powered vacuum tube that generates microwaves using the interaction of a stream of electrons with a magnetic field. The 'resonant' cavity magnetron variant of the earlier magnetron tube was invented by John Randall and Harry Boot in 1940 at the University of...
. It replaced Metox
Metox
The Metox, named after its manufacturer, was a pioneering high frequency very sensitive radar warning receiver manufactured by a small French company in occupied Paris, which could detect ASV transmissions from patrolling Allied aircraft. It is not clear whether the design was German or French or...
, which was incapable of detecting centimetric radar.
Telefunken
Telefunken
Telefunken is a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the Allgemeine Elektricitäts-Gesellschaft...
built a simple detector named "Naxos" that could pick up 10 cm / 3 GHz
GHZ
GHZ or GHz may refer to:# Gigahertz .# Greenberger-Horne-Zeilinger state — a quantum entanglement of three particles.# Galactic Habitable Zone — the region of a galaxy that is favorable to the formation of life....
H2S radar
H2S radar
H2S was the first airborne, ground scanning radar system. It was developed in Britain in World War II for the Royal Air Force and was used in various RAF bomber aircraft from 1943 to the 1990s. It was designed to identify targets on the ground for night and all-weather bombing...
transmissions, and a more sophisticated detector named "Korfu" with greater range and accuracy.
Korfu saw little use, but Naxos saw widespread service. There were two different types of Naxos. "Naxos Z" was developed for night fighters and mounted in a teardrop-shaped blister on top of the fighter's canopy. It could detect an RAF bomber from much longer range than FuG 227 Flensburg
Flensburg radar detector
The FuG 227 Flensburg was a German passive radar receiver developed by Siemens AG and introduced into service in Spring 1944. It used wing-mounted dipole antennae and was sensitive to frequencies of 170-220 MHz...
. Another version, the S-band (2500-3700 MHz, 12–9 cm wavelength) FuMB7 Naxos U, was provided to U-boats to allow them to detect 10 cm / 3 GHz ASV (air to surface vessel) radar, though by that time the U-boats were entirely on the defensive and it did them only a little good. By one of those weird coincidences which occur in wartime, the U-Boats received their Naxos 10 cm detectors on the same day that RAF Coastal Command deployed its first 3 cm ASV radar sets. Naxos was further hobbled by the fact that it proved very fragile in field conditions, and working out the bugs ended up being a difficult task.
The "Naxos ZR" was fitted to the tails of German night fighters to warn them if they were being tracked by RAF De Havilland
De Havilland
The de Havilland Aircraft Company was a British aviation manufacturer founded in 1920 when Airco, of which Geoffrey de Havilland had been chief designer, was sold to BSA by the owner George Holt Thomas. De Havilland then set up a company under his name in September of that year at Stag Lane...
Mosquito
De Havilland Mosquito
The de Havilland DH.98 Mosquito was a British multi-role combat aircraft that served during the Second World War and the postwar era. It was known affectionately as the "Mossie" to its crews and was also nicknamed "The Wooden Wonder"...
night intruders fitted with the AI Mk.IV radar and its derivatives.
Naxos receivers were also combined with the parabolic antennas from Würzburg radar
Würzburg radar
The Würzburg radar was the primary ground-based gun laying radar for both the Luftwaffe and the German Army during World War II. Initial development took place before the war, entering service in 1940. Eventually over 4,000 Würzburgs of various models were produced...
systems to produce a long-range receiver tuned to the British Oboe
Oboe (navigation)
Oboe was a British aerial blind bombing targeting system in World War II, based on radio transponder technology. Oboe accurately measured the distance to an aircraft, and gave the pilot guidance on whether or not they were flying along a pre-selected circular route. The route was only 35 yards...
radio navigation
Radio navigation
Radio navigation or radionavigation is the application of radio frequencies to determine a position on the Earth. Like radiolocation, it is a type of radiodetermination.The basic principles are measurements from/to electric beacons, especially...
system. The system later used a Domeyer receiver and became the Naxburg system. Oboe broadcast pulses from the aircraft that needed to be powerful enough to be received by ground stations in the UK. This made them relatively easy to pick out at short ranges, as long as the receiver was tuned to a suitable frequency. When such a signal was detected, false pulses identical to those received from the aircraft were re-broadcast from the ground. Stations in the UK thus received two or more signals for every signal they sent out, which confused the detectors. The British had used a similar system against the German navigation systems earlier in the war.