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3.5  Lightning protection 

For effective protection against lightning strike it is advisable to connect the antenna supporting 
structure to a ground electrode that is suitable for lightning protection. In the case that the 
building or adjoining buildings and/or mast on which the antenna is installed is already lightning 
protected it is sufficient to connect the antenna supporting structure to this grounding net. Also 
the antenna cable should be protected with an impulse suppressor at the point where the antenna 
cable enters the building. This impulse suppressor should be grounded properly. When in doubt 
leave lightning protection to skilled consultants and/or companies. 

Summary of Contents for 45100

Page 1: ...Datawell Waverider Receiver Manual RX D type 2 from serial no 45100 October 14 2015 Service Sales Voltastraat 3 1704 RP Heerhugowaard The Netherlands 31 72 534 5298 31 72 572 6406 www datawell nl...

Page 2: ...2 Check if mains supply matches with the specifications of the device...

Page 3: ...2 Checking the receiver alignment 14 4 2 1 Realignment procedure 15 4 3 Changing the reception frequency 16 4 3 1 Crystal exchange procedure 16 4 4 W ves21 and SeaSaw21 16 5 Troubleshooting 17 5 1 Pow...

Page 4: ...4...

Page 5: ...tter The RX D2 is tuned to the reception frequency using exchangeable receiving crystals The RX D2 is connected to a PC running W ves21 using RS232 In Chapters 2 3 and 4 of this manual the installatio...

Page 6: ...6...

Page 7: ...The front panel contains the LCD and the speaker test button The back panel contains the following connectors Socket for mains supply with fuses Audio out for beat note monitoring Female 9 pin RS232 c...

Page 8: ...8...

Page 9: ...t The transmitter antenna is vertically polarised therefore the receiving antenna must also be mounted vertically For the assembly of the antenna and adjustment of its length to the transmit frequency...

Page 10: ...signal and or high local noise or interference the use of a directional antenna can be considered The sensitivity of such an antenna is 3 dB higher in the direction of the buoy Interference and noise...

Page 11: ...joining buildings and or mast on which the antenna is installed is already lightning protected it is sufficient to connect the antenna supporting structure to this grounding net Also the antenna cable...

Page 12: ...12...

Page 13: ...has just re synchronized The receiver is now validating the buoy signal heave 0153 cm This message see figure 4 1 indicates that the receiver is correctly synchronized and receiving data The heave va...

Page 14: ...dible indication of the signal quality A 1500 Hz frequency modulated beat note should be heard against a clean background none or clean noise without any sign of interference or noise bursts The speak...

Page 15: ...that adjusts the receiver alignment is accessible from the underside of the receiver To get access only the bottom plate of the receiver needs to be removed The bottom plate is fixed by four flat scre...

Page 16: ...the receiver is using high or low mixing see paragraph 4 2 Disconnect power For safety reasons first remove power by disconnecting the power cable and all other cabling from the receiver Disassemble...

Page 17: ...bling Check if mains or backup voltages are OK Check both fuses Replace fuses if necessary and always both at the same time even if one of them seems OK1 The fuses are accessible from the backside of...

Page 18: ...ed by the buoy transmitter and the spectrum must be shared with other users It is entirely possible that some frequencies are unusable in your vicinity due to other users If this is the case consider...

Page 19: ...nnector 50 nominal input impedance Power Supply AC power 100 240 VAC 50 60 Hz 3 0W avg 4 5W max Digital backend Link bit rate 81 92 bits per second Type of modulation FSK Error detection BCH 63 51 err...

Page 20: ...20...

Page 21: ...04 P Heerhugowaard The Netherlands Tel 31 72 534 5298 Fax 31 72 572 6406 E mail sales datawell nl Service Voltastraat 3 1704 P Heerhugowaard The Netherlands Tel 31 72 571 8219 Fax 31 72 571 2950 E mai...

Page 22: ...f a buoy receiver system can be made with the numbers in decibels or decibel milliwatts and the calculation at the end of this appendix Figure A 1 H F buoy to receiver data link system A 1 Buoy transm...

Page 23: ...d Directional Waverider buoys except for the DWR G 0 4m The seawater around the buoy or an other artificial ground plane is an important part of the antennas counterpoise and is therefore absolutely n...

Page 24: ...e weaker the received buoy signal the more sensitive the communication link will be to errors induced by mechanisms such as interference and distant buoys transmitting at the same frequency Technical...

Page 25: ...ource for instance the spark ignition from a car Over the last 20 years interference has increased significantly and over the next 20 years there is no reason to assume that this increase will be halt...

Page 26: ...tions use an attenuator7 at the input of the receiver use a directional antenna and or contact our service department Error an out of band interferer damages my data and the buoy signal is weak Soluti...

Page 27: ...a higher and or closer to the buoy combat interferers as described above A 3 6 Existence of other buoy transmitters on the same frequency It is possible that buoys from your or from another organisati...

Page 28: ...he modulation type and protocols used for the others buoy to receiver data link From this we see that predicting data link quality in an interference limited case is a specialist job At Datawell we de...

Page 29: ...ragraphs but only if the transmission range is noise thus not interference limited The maximum difference between the transmitted power 17 dBm and the minimum receiving power 116 dBm is 133 dB Thus th...

Page 30: ...ee A 2 136 dB distance over fresh water ice see A3 1 10 dB max wave height 8 meters see A 3 5 10 dB some obstacles 10 dB normal antenna height of 20 meters 8 dB gain of receiving antenna see A 4 which...

Page 31: ...eceived and corrected 64 bit vector grouped in four words of 16 bits each The meanings of each of the fields in the message are SS status see below NN line number cyclically counting from 00 to FF VVV...

Page 32: ...mode corresponding to WAREC command mode 34 hexadecimally formatted unaltered buoy messages Hence the RX D2 can neither be stopped nor commanded to output a spectrum or system file This data filterin...

Page 33: ...Processor IFD Instantaneous Frequency Deviation IP Internet Protocol GPS Global Positioning System HF High Frequency Hz Hertz FER Frame Error Rate FSK Frequency Shift Keying LAN Local Area Network mem...

Page 34: ...34 Appendix E Receiving antennas E 1 Standard groundplane antenna Figure E1 Standard groundplane antenna...

Page 35: ...35 Adjust the antenna L1 and L2 lengths to the transmit frequency of the buoy Figure E2 Standard groundplane antenna continued...

Page 36: ...36 E 2 Directional Antenna 25 45 MHz Figure E3 Directional quarter wave antenna...

Page 37: ...y placing a reflector behind the receiving antenna to make it directional The antenna as shown has a forward gain of 3 dB that is equivalent to doubling the transmitter power More important is that it...

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