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Japanese naval radar

Discussion in 'Naval Warfare in the Pacific' started by T. A. Gardner, Aug 19, 2003.

  1. T. A. Gardner

    T. A. Gardner Genuine Chief

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    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.
     
  2. Sarge1

    Sarge1 Member

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    where did you get that info?

    [ 24. August 2003, 08:14 AM: Message edited by: Sarge ]
     
  3. T. A. Gardner

    T. A. Gardner Genuine Chief

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    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.
     
  4. Kai-Petri

    Kai-Petri Kenraali

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  5. Poppy

    Poppy grasshopper

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    Ha ha! Excellent. I was going to create a new thread using the same title and thought : maybe I should search. It's great having the answers to my thoughts so quickly.
    Anyhoo, some of the sets mentioned above were from 1942 onwards. Did the Japanese have any radar aboard during the Guadalcanal period? 'Cause I thought they didn't. I know the US did but was troublesome at times. US also had the codes for JP communications. .. How were the JP able to make night rat runs, bombardments, engagements when they had no radar and comm leaks?... Were the JP led by more capable admirals in that campaign?
     
  6. Poppy

    Poppy grasshopper

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    I should have known my question was already kinda covered .- Japanese night tactics-had some good stuff in it.
     

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