The German radio and radar electronic components reflect the considerable engineering thought given to mechanical design for the purpose of saving space and providing installation and maintenance accessibility.  
          The only means provided for communication between the radar and the Conning Tower in which the TDC is installed consists of a voice tube.  It is assumed that the German did not seriously associate radar with fire control equipments.  
          Installation practices are considered inferior to USN practices.  
July, 1946
- 1 -


  A.  Introduction  
          The purpose of this report is to present the number, type function and methods of installation of German radio and radar equipment installed in this type vessel.  
          German equipments have been made available to the Naval Research Laboratory for detailed exploitation either from the Shipyard or directly from Germany.  In addition, N.R.L. personnel have made field tests of installed equipments on German vessels operated by USN personnel.  At present only preliminary reports from the Laboratory are available to the Shipyard, these are presented on Encl. (A) to N.R.L., Conf. ltr. C-EF30 (R130A) to CNO of 29 May 1946.  
          In addition, separate reports have been prepared by the Shipyard and have already been distributed.  These reports are written on the following equipments  
                  1.  Receiver Type ELA 1012 (Broadcast Res.)  Report 2G-GEN-S67A of January 1946  
                  2.  Receiver Type E52b-1 Ln 21000-6 (Short Wave Recr.)  Report 2G-GEN-S67B of January 1946  
                  3.  Transmitter Type T-200-FK39c  (200 Watt - 3 to 23 megacycles)  Report 2G-GEN-S67C of February 1946.  
  B.  Descriptive  
          The Germans provided two separate rooms for installation of electronic equipment, namely, a Sound Room and a Radio Room.  The only means provided for communication between these rooms and the C.T. and C.R. is a voice tube.  
           All components of radio and radar systems are located in one or the other of these rooms.  In nearly all vessels of this type the following equipments are located in the Radio Room.  
                  1.  Radio Transmitter - 200 Watt; 3-24 Megacycles Type - T-200-FK39c Manufactured by Telefunken.  
                  2.  Radio Transmitter - 150 Watt; 300-600 Kilocycles  Type 21131S Manufactured by Telefunken.  
                  3.  Short Wave Receiver 1.5 - 25 Megacycles  Type E52b - Ln 21000-6 Manufactured by Cologne.  
     - 2 -


                  4.  Broadcast Radio Receiver Type ELA1012  Manufactured by Telefunken.  Used mainly as entertainment broadcast receiver.  Frequency bands as follows:  
Band I
14 - 48
Band II
47 - 166
Band III
515 - 1800
Band IV
150 - 400
                  5.  Short Wave Radio Receiver, 20-1000 Meters  Type E 437 S4/41  
                  6.  Radar Surface Search Type SG200.  Consists of the following separate units:  
                          a)  Transmitter - Type S-200 O.P. Freq. 68cm Repetition Rate 450 C.P.S.  
                          b)  Receiver Type S-6-200  
                          c)  Indicator ("A" Type Presentation)  Provision made for lobe switching, but device not present in antenna system.  
                          d)  Voltage Regulator Panel Type SGLE053/1  
                          e)  Control Unit - F200  
                          f)  Antenna Switch and Duplexer  
                          g)  Antenna - Similar to old S.C. Antenna.  Houses in Bridge Fairwater and is hoisted by compressed air.  Entrance thru pressure hull in Control Room.  Hand training only from Radio Room  
                  7.  Radio Direction Finder Type T3P11a38 consists of the following units:  
                          a)  Regenerative Receiver  
                                  Bands I-IV 70-1200 Kilocycles  
                                  Band V 15-33 Kilocycles (used under water)  
                          b)  Power Supply Unit Type EN410S  
                          c)  Antenna - Direction Finder Loop.  Hand training from Radio Room.  360° Train - Then reverse Slip Rings not used.  Gyro input provides means for obtaining true and relative bearing.  Loop is housed in Bridge Fairwater and is hoisted by compressed air.  Entrance thru pressure hull in Control Room.  
                  8.  220 V 50 Cycle and 110 V D.C. Distribution Panel.  
     - 3 -


                  9.  Antenna Connection Boxes and Patch Cords.  
                  10.  Portable Typewriter  
                  11.  Control Loudspeaker for combination 1MC and Entertainment Broadcast.  
          The following radio and radar system components are located in the Sound Room.  
                  1.  All Wave Radio Receiver 20-20,000 Kilocycles.  Manufactured by Telefunken.  Estimated to be at least a 12 year old model.  
                  2.  Emergency Radio Transmitter, 40 Watt 20-80 Meter.  Control Panel type EBG LO 39a  
                  3.  VHT Trans-Recr. Freq. Range unknown, Type 10UK39.  Crystal controlled.  Consists of Transmitter Receiver and Power Supply.  
                  4.  Radar Detector Equipment.  Consists of the following units:  
                          A.    (a)  2 Tunis Antenna (one spare)  These units are portable and consist of a back to back 9CM Dipole and Reflector and a 3 CM Horn.  Detector units for each system are mounted on the back of each of the two antennae.  These antennae are mounted on a wooden stick on the bridge and are rotated by hand.  Both sections of the antenna feed thru their respective crystal detectors into portable cables which are led down thru the Bridge Hatch to jacks in the C.T. and hence to the Amplifiers in the Sound Room listed as (b) and (c) below.  
                                  (b)  3 CM Amplifier and Power Supply  
                                  (c)  9 CM Amplifier and Power Supply  
                          B.  165 - 175 CM Detector and amplifier antenna mounted on Schnorchel.  Name Plate Data or Instruction Books not available on above equipments.  
                  5.  Life Boat Portable Transmitter "Mae West" type Freq 600 Meter.  Has automatic "SOS" button.  Antenna supported by inflated balloons.  
          Inspection of German circuit design indicates that progress has not been as rapid nor as advanced as that of USN.  However, the attention to mechanical design is particularly noteworthy.  These features are  
     - 4 -


  discussed in detail in the individual reports prepared by the Shipyard and it is presumed will be discussed in reports to be prepared by the Naval Research Laboratory.  
          Installation practices observed are as follows:  
                  1.  Adequate apace is provided for operation and maintenance of equipments.  
                  2.  All components are mounted on bonded rubber mounts in compression, tension or shear for shock protection.  
                  3.  The majority of the above mounts are secured to the wood compartmentation, on the heavier units they are secures to the steel deck as well.  
                  4.  Rubber covered shielded cables, single and multi conductor, not heat and flame retardant, are employed in electronic circuits.  
                  5.  The shields of the above cables are thoroughly grounded at each point of entrance to components.  
                  6.  Power Training is not provided in any system.  
                  7.  Lead and cable identification is consistent with German practices as discussed in Report 2G-9C-S28.  
                  8.  Terminal blocks as described in Report 2G-9C-S65 are used extensively.  
                  9.  Connections are generally made by tinning the end of the lead, rather than employing terminals.  
                  10.  Except for antenna leads all cables are run in community cable banks.  
                  11.  Cable supports in way of the radio and sound rooms are secured to the wooden compartmentation by means of wood screws.  
                  12.  The only radio and radar leads run external to the two rooms are the power supplies and the antenna leads.  
          The antennae listed below are installed:  
                  1.  Surface search radar bedspring type.  Similar to old SC type.  Hoisted by air from Control Room.  Trained by hand from Radio Room.  
                  2.  Radio Direction Finder Loop Antenna.  Hoisted by air from Control Room.  Trained by hand from Radio Room.  On some vessels a stub antenna for VHF equipment is mounted on the loop.  
     - 5 -


                  3.  Dipole Antenna for radar intercept equipment is mounted on the Schnorchel.  
                  4.  Wire rope antenna for radio transmission and receiving as follows:  
                          a)  Transmitting antenna - Runs from forward bridge structure to within a few feet of the bow on centerline.  
                          b)  Receiving Antennae - Two installed, one port and one starboard, run from after bridge structure to within a few feet of the stern on each side.  They are relatively low and it is believed their usefulness would be diminished in a heavy sea.  
          The three wire rope antennae are not brought thru the pressure hull in a common trunk.  Each antenna is brought thru the pressure hull individually.  For detailed information with regard to the German antennae layout and method of bringing the wire rope antennae thru the pressure hull reference should be made to the:  "Beschreibung und Betriebvorschrift der Bu M Anlage U Boote Typ IXC und IXD2"  (Description and Operating Instructions for Interior Communication Systems Submarines Type IXC and IXD2), and to:  "Beschreibung und Betriebvorschrift Antennenanlagen auf U1228 (Description and Operating Instructions for Antennae Systems on U1228).  
          Antennae leadings, transmitter antennae connections and receiver antennae connections are brought together in suitably designed jack boxes.  Patch cords are used to make the desired connections.  
          German practices, materials used as well as insulator design in the antennae systems inspected offer nothing unique or new to USN techniques.  
          Power supplies are obtained from the sources indicated below.  A motor generator of the type used for the power supply of the 200 Watt transmitter type T200 FK39C has been shipped to the Bureau of Ships Code 660 for detailed exploitation and reference should be made its report when it becomes available.  
     - 6 -


          The merit of the different installed systems must necessarily await the completion of the bench and field tests by U.S.L. personnel.  
          Early indications are that the equipments are electrically at least equal to comparable USN equipments and mechanically, the designs with regard to space, access and control are definitely superior to USN equipments.  
           The German practice of providing a separate Sound Room is noteworthy particularly when considered in light of relatively elaborate installations in USN submarines.  
          The individual detail installation practices rest on their own merit, if any.  
     - 7 -



Click the icons to view the associated records

Return to the Design Studies page