Just a list of them. Someone might find this useful. One of these days I will add photos and drawings of most of these, just haven't got around to hooking up the new scanner....

The Japanese Navy adopted the term Dentan (from Denpa for electronic wave and Tanshingi for detection / search). Each set was designated by type and function (Gô), model (Gata), and modification (Kai). The Gô types were:

1 Gô Land air search / early warning
2 Gô Shipboard air search / early warning
3 Gô Shipboard surface search and fire control
4 Gô Land anti-aircraft fire control
5 Gô Airborne radar sets
6 Gô Other sets

For example: The 1 Gô 1 Gata Dentan radar would be a model 1 land air search / early warning type radar. For brevity the designations in use would often be shortened to 11 Gô Dentan for the example.



Japanese Naval Radars Described:

1 Gô 1 Gata Fixed position air search radar, land based.
Wavelength: 3m
Frequency: 100 MHz (in operation this varied from 92 – 108 MHz)
PRF: 750 (varying in use from 530 to 1250)
Pulse length: 10 – 30 µsec
Peak power: 40kw
DRange: 1 – 2 km
DBearing:
Antenna type:
Production: 30 units
Development: Development began pre-war. All sets delivered prior to December 1941.
Performance: Group of aircraft 250 km, single aircraft 130 km

1 Gô 2 Gata Land based mobile air search radar

Wavelength: 1.5m
Frequency: 200 MHz (in operation this varied from 187 – 214 MHz)
PRF: 1000 (varying in use from 750 to 1500)
Pulse length: 3 – 20 µsec
Peak power: 5kw
DRange: 1 – 2 km
DBearing:
Antenna type: Mattress
Production: 300 units
Development: Development began pre-war.
Performance: Group of aircraft 100 km, single aircraft 50 km, surface search 18km.
Notes: Uses UN 954 detector circuit. Transmitter uses 2C oscillator with 2 T-310 tubes.

1 Gô 3 Gata Mobile land based air search early warning

Wavelength: 2m
Frequency: 150 MHz (in operation this varied from 146 – 165 MHz)
PRF: 500 (varying in use from 400 to 600)
Pulse length: 10 µsec (3 – 12 µsec in service)
Peak power: 10kw
DRange: 2 – 3 km
DBearing: 10°
Antenna type: Mattress
Production: 1000 units
Development: Developed from the army

Performance: Group of aircraft 100 km, single aircraft 50 km, surface search 18km.
Notes: Uses UN 954 RE-3 detector circuit. Transmitter uses 2C oscillator with 2 T-311 tubes.

1 Gô 4 Gata Land based air search radar

Wavelength: 6 m
Frequency:
PRF:
Pulse length:
Peak power:
DRange:
DBearing:
Antenna type:
Beam dimensions:
Production:
Development:
Performance: Group of aircraft 450 km, single aircraft 250 km,
Notes:

2 Gô 1 Gata 1 Kai Shipboard air search radar

Wavelength: 1.5m
Frequency: 200 MHz (in operation this varied from 187 – 214 MHz)
PRF: 1000 (varying in use from 750 to 1500)
Pulse length: 3 – 20 µsec
Peak power: 5kw
DRange: 1 – 2 km
DBearing: 20°
Antenna type: Mattress 6 Gata antenna
Beam dimensions: 34° x 60°
Production: units
Development: August 1942
Performance: Group of aircraft 100 km, single aircraft 50 km, surface search 18km.
Notes: Development of the 1 Gô 2 Gata Dentan land based radar. Installed on many major fleet units from August 1942 onward.

2 Gô 1 Gata 2 Kai Shipboard air search radar

Wavelength: 1.5m
Frequency: 200 MHz (in operation this varied from 187 – 214 MHz)
PRF: 1000 (varying in use from 750 to 1500)
Pulse length: 3 – 20 µsec
Peak power: 5 kW
DRange: 1 – 2 km
DBearing:
Antenna type: Mattress 6 Gata antenna
Beam dimensions: 34° x 60°
Production: units
Development: April 1943
Performance: Group of aircraft 100 km, single aircraft 50 km, surface search 18km.

2 Gô 1 Gata 3 Kai Shipboard air search radar

Wavelength: 1.5m
Frequency: 200 MHz (in operation this varied from 187 – 214 MHz)
PRF: 1000 (varying in use from 750 to 1500)
Pulse length: 3 – 20 µsec
Peak power: 30 kW
DRange: 1 – 2 km
DBearing: 20°
Antenna type: Mattress 7 Gata
Beam dimensions: 34° x 60°
Production: 2 units
Development: Experimental August 1943 to February 1944. Unsatisfactory performance all research ended by April 1944.
Performance: Group of aircraft 100 km, single aircraft 50 km, surface search 18km.
Notes: Experimental development of the 21 Gô Dentan for surface gunnery. Fitted to Nachi and Yamato. Used the 7 Gata antenna with boosted power. Performance was insufficiently good to use as a fire control set. Discontinued in development. Replaced by the 22 Gô Dentan 4 Kai S.

2 Gô 1 Gata 4 Kai Shipboard air search / surface search radar

Wavelength: 1.5m
Frequency: 200 MHz (in operation this varied from 187 – 214 MHz)
PRF: 1000 (varying in use from 750 to 1500)
Pulse length: 3 – 20 µsec
Peak power: 30 kW
DRange: 1 – 2 km
DBearing: 20°
Antenna type: Mattress 7 Gata
Beam dimensions: 34° x 60°
Production: 1 unit
Development: Experimental. Follow on to the 21 Gô Dentan 4 Kai. February 44 to May 44 when development ended. Unsatisfactory performance.
Performance: Group of aircraft 100 km, single aircraft 50 km, surface search 18km.
Notes: Experimental development of the 21 Gô Dentan for surface gunnery.

2 Gô 1 Gata 5 Kai Shipboard air search / surface search radar

Wavelength: 1.5m
Frequency: 200 MHz (in operation this varied from 187 – 214 MHz)
PRF: 1000 (varying in use from 750 to 1500)
Pulse length: 3 – 20 µsec
Peak power: 30 kW
DRange: 1 – 2 km
DBearing: 20°
Antenna type: Mattress 7 Gata
Beam dimensions: 34° x 60°
Production: 1 unit
Development: Experimental February 44 to Sept 44. Unsatisfactory performance all research ended by October 1944.
Performance: Group of aircraft 100 km, single aircraft 50 km, surface search 18km.
Notes: Experimental development of the 21 Gô Dentan for surface gunnery. Fitted on the cruiser Kiso. Used the 7 Gata antenna with boosted power.

2 Gô 2 Gata 1 Kai Shipboard surface search radar

Wavelength: 10 cm
Frequency: 3 GHz (varying in service between 2.8 – 3.125 GHz)
PRF: 2500
Pulse length: 2 – 10 µsec
Peak power: 0.5kw
DRange: 700 m
DBearing: 2 - 5°
Antenna type: Double horn antenna
Beam dimensions: 38° conical
Production: Few
Development: Early 1942
Performance Surface search 22km. .
Notes: A total of approximately 400 22 Gô Dentan Kai 1 – 3 models were produced. The 1 Kai model suffered from lack of power and remained experimental. Replaced in service by the 22 Gô 2 Kai with boosted power.

2 Gô 2 Gata 2 Kai Shipboard surface search radar

Wavelength: 10 cm
Frequency: 3 GHz (varying in service between 2.8 – 3.125 GHz)
PRF: 2500
Pulse length: 2 – 10 µsec
Peak power: 2 kW
DRange: 700 m
DBearing: 2 - 5°
Antenna type: Double horn antenna
Beam dimensions: 38° conical
Production: Approximately 100 units
Development: June 1942 to December 1942
Performance Surface search 22km. Detection of large ships 35 km
Notes:

2 Gô 2 Gata 3 Kai Shipboard surface search radar

Wavelength: 10 cm
Frequency: 3 GHz (varying in service between 2.8 – 3.125 GHz)
PRF: 2500
Pulse length: 2 – 10 µsec
Peak power: 2 kW
DRange: 700 m
DBearing: 2 - 5°
Beam dimensions: 38° conical
Antenna type: Double horn antenna
Production: Approximately 200 units
Development: October 1942 to June 1943
Performance Surface search 22km. Detection of large ships 35 km
Notes:

2 Gô 2 Gata 4 Kai M Shipboard surface search radar

Wavelength: 10 cm
Frequency: 3 GHz (varying in service between 2.8 – 3.125 GHz)
PRF: 2500
Pulse length: 2 – 10 µsec
Peak power: 2 kW
DRange: 700 m
DBearing:
Antenna type: Mattress 6 Gata antenna
Beam dimensions: 38° conical
Production: units
Development: December 1942 to December 1943
Performance Surface search 22km. Detection of large ships 35 km
Notes: Experimental development to produce a fire control radar. Unsuccessful.

2 Gô 2 Gata 4 Kai S Shipboard surface search and fire control radar

Wavelength: 10 cm
Frequency: 3 GHz
PRF: 2500
Pulse length: 2 – 10 µsec
Peak power: 2 kW
DRange: 100 m
DBearing: 0.5 to 1°
Antenna type: Double horn antenna. Diameter enlarged to 80 cm on receiving horn.
Beam dimensions: 38° conical
Production:
Development: December 1943 to July 1944
Performance Surface search 22km. Large units detected up to 35 km.
Notes: First successful fire control radar. Installed late war on most major fleet units. Used super heterodyne receiver replacing previous auto heterodyne unit. Voltage stabilization was provided. Service issue began in August 1944.

2 Gô 3 Gata Shipboard surface search radar

Wavelength: 58 cm
Frequency:
PRF:
Pulse length: µsec
Peak power: 5 kW
DRange: 50 m
DBearing: 1°
Antenna type: 2 x 1.7 m parabolas (1 transmit, 1 receive).
Production: 1 or 2 units
Development: October 1943 to March 44
Performance Surface search 13 km. Detection of large ships 30 km
Notes: Japanese development of the German Würzburg radar. Experimental. Development ended in March 1944.

2 Gô 4 Gata Shipboard surface search radar

Wavelength: 28 cm
Frequency:
PRF:
Pulse length:
Peak power: 5 kW
DRange:
DBearing:
Antenna type:
Beam dimensions:
Production:
Development: Early 1944 to April 45 when research stopped.
Performance:
Notes: A development of the 2 Gô 3 Gata with shortened wavelength. Experimental only.

3 Gô 2 Gata Land based fire control radar

Wavelength: 10 cm
Frequency: 3 GHz (varying in service between 2.8 – 3.125 GHz)
PRF: 2500
Pulse length: 2 – 10 µsec
Peak power: 2 kW
DRange: 100 – 250 m
DBearing: 0.5°
Antenna type: Triple square horn antenna (1 transmit over 2 receivers)
Beam dimensions: conical
Production: 30 units
Development: February 1944 to September 1944
Performance: Surface search 30 km. Detection of small ships 13 km
Notes: Derived from the 22 Gô Dentan for coastal defense use. Fixed mounting.

3 Gô 1 Gata Land based fire control radar

Wavelength: 10 cm
Frequency: 3 GHz (varying in service between 2.8 – 3.125 GHz)
PRF: 2500
Pulse length: 2 – 10 µsec
Peak power: 2 kW
DRange: 100 – 250 m
DBearing: 0.5°
Antenna type: Parabolic dish
Beam dimensions: conical
Production: Not proceeded with.
Development: Mid 1944 to March 1945.
Performance:
Notes: A development of the 32 Gô Dentan set. Experimental only.

3 Gô 3 Gata Land based fire control radar

Wavelength: 10 cm
Frequency: 3 GHz (varying in service between 2.8 – 3.125 GHz)
PRF: 2500
Pulse length: 2 – 10 µsec
Peak power: 2 kW
DRange: 100 – 250 m
DBearing: 0.5°
Antenna type: Triple square horn antenna (1 transmit over 2 receivers)
Beam dimensions: conical
Production: Not proceeded with.
Development: Mid 1944 to January 1945.
Performance:
Notes: A development of the 32 Gô Dentan set. Experimental only.


4 Gô 1 Gata Land based AA search and fire control radar

Wavelength: 1.5 m
Frequency: 200 MHz
PRF: 2000
Pulse length: 3 µsec
Peak power: 13 kW
DRange: 50 – 100 m
DBearing: 1 – 1.5°
Antenna type:
Beam dimensions:
Production: Approximately 80 units
Development: October 1942 to August 1943
Performance: Detection of single aircraft at 20 km.
Notes: Developed from US SCR 286 and British GL II gun laying radars captured in the Philippines and Malaysia.

4 Gô 2 Gata Land based AA search and fire control radar

Wavelength: 1.5 m
Frequency: 200 MHz
PRF: 1000
Pulse length: 3 µsec
Peak power: 30 kW
DRange: 50 - 100 m
DBearing: 0.5°
Antenna type:
Beam dimensions:
Production:
Development:
Performance: Range on group of aircraft 30 – 40 km. Single aircraft at 15 – 20 km.
Notes: Improved development of the 41 Gô Dentan set.

4 Gô 3 Gata Land based air search radar

Wavelength: 1.5 m
Frequency: 200 MHz
PRF: 1000
Pulse length: 2 µsec
Peak power: 5 kW
DRange:
DBearing:
Antenna type:
Beam dimensions:
Production:
Development:
Performance:
Notes: Direct copy of the Army Tachi 1 set. Used for searchlight control. Unsatisfactory performance.


6 Gô 1 Gata Airborne surface search radar

Wavelength: 2 m
Frequency: 150 MHz (140 – 160 MHz in service)
PRF: 1000 (varies between 700 and 1200 in service)
Pulse length: 3 - 10 µsec
Peak power: 3 - 6 kW
DRange:
DBearing:
Antenna type: Yagi array along aircraft sides.
Beam dimensions:
Production: Over 2000 units.
Development:
Performance: Large surface targets up to 70 km.
Notes: Primary airborne search radar for IJN aircraft. Manufacturer’s designation H-6.

3 Gyoku Airborne intercept radar

Wavelength: 2 m
Frequency: 150 MHz (140 – 160 MHz in service)
PRF: 1000 (varies between 700 and 1200 in service)
Pulse length:
Peak power:
DRange:
DBearing:
Antenna type: Yagi array
Beam dimensions:
Production:
Development: Under development from late 1944.
Performance:
Notes:

Japanese ESM sets

Officially these were known as Denpa Tansakuki.
Kai 3 Metric wavelength ESM receiver

Detection range: 75 cm - 4 m
Detection frequency bandwidth:
Detection range: 300 km
Production:
Development: From early 1943. In service June 1943.
Notes: Used 2 “Metox” type non-directional antennas plus one “tennis racket” directional antenna. The two non-directional antennas were placed on the bridge wings of the ship while the rotating directional antenna was amidships. Manufacturer’s designation: E-27

3 Gata Centimetric wavelength ESM receiver

Detection range: 3 - 75 cm
Detection frequency bandwidth:
Detection range:
Production:
Development: From late 1943. In service January 1944.
Notes: Used the 49 Gô 4.5 cm parabolic dish antenna. Super heterodyne receiver.

where did you get that info?

[ 24. August 2003, 08:14 AM: Message edited by: Sarge ]

Friedman, Norman Naval Radar, Conway Maritime Press, London, 1981

Nakajima, Dr. S. The History of Japanese Radar Development to 1945 in Radar Development to 1945, Russell Burns ed., Peter Peregrinus, London, 1988.

Price, Alfred The history of US Electronic Warfare, vol. 1, The Association of Old Crows, 1984

Along with various articles in Warship, Warship International etc.

Site with some pics on different radar types

http://www.star-games.com/exhibits/j...neseradar.html

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