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(serial-number higher than 1000) with devices out of older generations, e.g. antenna unit N° xx-xx-0999 does not work with display unit N°xx-xx- 1001 and conversely due to the advanced technical standard! Manual RT-202...
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3.3 Serial RS-232 Data Interface / Data protocol 3.3.1 Interface data 3.3.2 Data output 3.3.3 Data input 3.3.4 Connector holding 3.3.5 Connecting cable Direction Finder PC 3.4 Installation of supplement devices 3.4.1 External speaker 3.4.2 Alarm bell 3.4.3 External ON/OFF switch Manual RT-202...
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4.4.1 Testing of nominal qualities on watercrafts or land vehicles 4.4.2 Testing of nominal qualities, stationary use. 5 AVAILABLE ACCESSORIES 6 DECLARATION OF CONFORMITY 7 APPENDIX 7.1 Test protocol 7.2 Drawing for mounting of the Display Control Unit Manual RT-202...
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List of all possible serial messages Pin holding serial connector on Direction Finder Serial connection cable for Direction Finder Display of actual battery voltage or power supply Approach to the transmitter despite 30° bearing error Stencil drawing for mounting of the display unit Manual RT-202...
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Page 7 of 35 Thank you very much for buying a direction finder of the company RHOTHETA Elektronik GmbH. We would like to ask you now to read this operating manual completely and carefully in order to avoid possible damages caused by incorrect operation or assembly.
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1.3 Front view of the Display Control Unit (DCU) Front view of the Display Control Unit (DCU) in standard POM-version Operating elements of the Direction Finder RT-202 (Look for more detailed description in the chapters) On/Off - switch of the direction finder.
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(15) Display of the LEVEL of the incoming signal by four green LED’s. (16) SIGNAL squelch indicator, red LED lit when signal is received. (17) Direction finding indication by 36 red LED’s. (18) Red warning-LED for intolerable frequency deviation of the received signal (> 5.5 kHz). Manual RT-202...
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D-Sub socket “Power / Remote” for power supply optional connection of a PC (serial RS-232) an external speaker activation of alarm an external ON/OFF- switch Screw socket for fixing the display unit (4x M4) and connection for ground Manual RT-202...
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In undisturbed wave field and sufficient field strength. The bearing value results by changing the direction of incidence, in course of which the antenna is turned on a rotating device to exclude environmental influences on the DF value. Receiving very low signal levels can increase attack time considerably! Manual RT-202...
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/ alarm: < 1 V DC (I : ≈100 mA) max. The audio signal is superimposed upon the antenna scanning signal. This can affect considerably the unintelligibility of voice signals. ELT-signals will not be affected remarkably. Manual RT-202...
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- app. 20 N at 180 km/h wind speed Mast flange Cable strain relief clamp (optional) Direction finder antenna It is recommended to seal the mast tube, to protect the connectors from moisture. For this purpose the additional available mast sealing can be used. Manual RT-202...
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Plug the bolts of the display unit into the assigned drill holes so that the surfaces have full contact. Now the display unit should be pressed in correct position onto the mounting surface whilst mounting the washers and nuts from the inside. Tighten the nuts, use LOCTITE-screw locking if necessary. Manual RT-202...
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The Display Control Unit has to be grounded to the ground of the ship or land vehicle where it is mounted. This connection should be realised via one of the 4 screw sockets at the back side of the display case. Manual RT-202...
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Ground (GND) (GND) Remarks: maximum length of cable: app. 50 m. Cable shield to be connected with connector shield! If using a 10-wired cable it is recommended to put the power supply onto 2 conductors (pin 5). Manual RT-202...
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No water should come to the D-Sub connector. The D-Sub connector is not waterproof! If water comes into the antenna, the antenna will be destroyed! The standard antenna cable is only useable for normal mounting and must not be used for upside down mounting! Manual RT-202...
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Put the antenna onto the mast flange. Take care that the o-ring of the antenna head fits properly to it’s groove. Fix the nut slightly. The tube flange is made of PVC, suitable glue e.g.: Tangit of firm „Walter Sahlberg GmbH &Co“ Manual RT-202...
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10 mm box end wrench. Do not exceed a torque of 3 Nm. beam Do not bend antenna rods, it might cause bearing errors. domed nut ring rod socket (LOCTITE- screw locking) Antenna case Assembly of the antenna rods Manual RT-202...
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Adjusting of reference direction QTE: Is to be done like „adjusting the reference direction QDR“. The value of the local magnetic declination has to be subtracted from the nominal value. Manual RT-202...
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6 CR LF 5 CR LF L LF L LF L LF unaveraged direction (circa.4x) Status Receiving level Averaged direction = 245° = Receiving signal = 72% = 246° Example: time diagram of data output with existing receiving signal Manual RT-202...
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They give information about version of software, serial number of the device and all the settings of the EEProm. All serial data can be read under assistance of a PC and terminal programme (e.g. Terminal in Windows or Norton). Each message is displayed in a new line. Manual RT-202...
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(see 4.2.6 Operating Functions / Function > <) ELTIDENT_ON Automatic Distress-Signal-Identification is switched On/Off ELTIDENT_OFF (see 4.2.7 Operating Functions / Function >IDENT<) 3.3.4 Connector holding Seriell IN Seriell OUT Leave leftover pins unconnected! Pin holding serial connector on Direction Finder Manual RT-202...
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(by connection to PC connect in any case Pins 1-6-4 and 7-8) Seriell IN Seriell OUT Connection to RT-202 Connection to PC max. length of cable ca. 30ft Serial connection cable for Direction Finder 3.4 Installation of supplement devices See also chapter 2.2 >Power supply and Remote – interface<.
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4.1.3 Display > Level < Four green LED’s indicate the field strength of the incoming signal. The more LED’s are lit the better the reception of the emergency signal. Rough sea can cause short changes of strength of the signal level. Manual RT-202...
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3 kHz scanning sound and therefore not more suitable for speech recognition. A distress signal (distinct howling with periodically changing sound) will not be influenced remarkably. The signal device can be switched off. (See chapter 4.2.6 Function > < (Speaker) switch off / on speaker) Manual RT-202...
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By pressing the push-button >REPEAT< the display shows blinking the last found out bearing value. The bearing value refers to the heading direction at the moment of the last received signal. Take care when using the repeat function after changing hading. Manual RT-202...
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>switch off speaker< is not forgotten by mistake and the next emergency is recognised. 4.2.7 Function > IDENT < (Distress-Signal identification) By pressing the >IDENT<-button the Distress-Signal-Identification is switched ON/OFF. If the Distress-Signal-Identification is switched OFF, then all received signals are activating the Manual RT-202...
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Then increase the squelch level just until the noise becomes suppressed. Now the receiver is most sensitive for the bearing signal and less disturbed by other noises. During bearing this adjustment may have to be executed several times. Manual RT-202...
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(121.500 MHz) take extreme care not to cause alarm by mistake. It became naturalised for testing purposes to switch on the emergency transmitter before and after every whole hour for max. 5 min. Watch local regulations! Manual RT-202...
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Remark Even if there are considerable bearing errors (up to 45°) the watercraft will reach the lost person, just by heading the indicated direction. (See drawing) Approach to the transmitter despite 30° bearing error Manual RT-202...
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cable strain relief clamp Mast tube Mast tube reducer Mast tube connector connector Antenna cable Power/Remote-Cable including fuseholder Linking cable Direction Finder PC Data transfer modem Display software „Bearing display“ Manual RT-202...
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Page 33 of 35 6 Declaration of Conformity Manual RT-202...
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Page 34 of 35 7 Appendix 7.1 Test protocol (enclosed) 7.2 Drawing for mounting of the Display Control Unit (enclosed as stencil drawing) ø 7 . 5 8 . 3 Manual RT-202...
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Page 35 of 35 Stencil drawing for mounting of the display unit Manual RT-202...
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