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VOYAGE DATA RECORDER Questions & answers 2 GENERAL ISSUES DATA

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VOYAGE DATA RECORDER Questions & answers 2 GENERAL ISSUES DATA Powered By Docstoc
					Questions & answers 2
For AMI & AMI representatives

06/04/2006

Latest Q & A is available on the www.v-d-r.net web site guidance notes page. Right-click on the link.

VOYAGE DATA RECORDER
If any of you out there want to add a question and/or the answer YOU gave send me an email. Thanks to everybody who has contributed. Andrew Fairgrieve af@v-d-r.net Answer from the designer and some other contributors. The VDR, s-VDR, can only do what it is designed to do. I have deliberately designed it to be simple and low cost. Yes, by TUV laboratories UK, and passed all EMC, vibration, temperature and humidity tests to IEC 60945, 61996 and Lloyds special standard. And it has been tested by Qinetiq who issue the certificate of MED type-approval. This includes USCG approval. If you want a voyage management system then you will have to buy one. This is a SIMPLIFIED VDR which must operate independently of everything else on the ship. You could use the “all data” output from the VDR to feed your voyage management system. You could use the same output for your ECDIS, or your Portable Docking Aid. 4. We want to use the VDR for training purposes. Excellent! I thoroughly approve of this. For training purposes, take the data out of the VDR on to your own computer and use it how you wish. With the replay programs available you can analyse your own manoeuvres and incidents. 5. Can we keep a monitor continuously connected to the s-VDR? Could the electronics unit be flush mounted in a bridge console. No. A keyboard and mouse would be required to control the display and that is definitely not allowed. IEC 61996 requires password access to the s-VDR. Yes. We do not make a flush mount kit, you would have to devise your own, not difficult for a shipyard. Check you have allowed enough access space at the top and right hand side so the s-VDR’s panels can be removed. I suggest at least 15 cm, so you can use a screwdriver and put your hand in. 7. What about packing and shipping? • • • • Do NOT have the metal MEU enclosure screwed down inside the plastic box for shipment. o It will probably pull out the screws in transit. Wrap the metalwork in bubble wrap polythene to make it a snug fit inside the plastic enclosure Don’t forget all the fasteners, fixings and connectors. Do NOT ship the power unit with the batteries inside. o Their weight would surely destroy the power unit in transit

Comments or questions

GENERAL ISSUES
1. 2. “ But Mike said it would ……” Has the new MEU been tested for type approval?

3.

We want to use the VDR as a voyage management computer.

6.

DATA STORAGE, RECOVERY & REPLAY.
8. Conoco are used to having “removable media” (in their old non type-approved VDRs) which they can unplug and send

COPYING SAVED DATA TO A COMPUTER.
That is an old method of doing things, before the days of cheap laptop computers.

ashore.

There is no chance of adding removable media to the s-VDR for good design reasons. If you want to get the saved data plug in a laptop. This is the method recommended by the IMO and Marine Coast Guard Agency etc. NO. The VDR s-VDR should never be interrupted in its essential duties of continuous and independent recording. First you must copy the files from the s-VDR onto your own computer. It is a standard Ethernet connection. QUICK-CHECK REPLAY You can view and/or play all the saved data using only the programs available on a Windows PC. • Notepad for all the NMEA or AIS data • Imaging for radar picture • Media player for sound FULL REAL-TIME REPLAY We have software available to run on a Windows PC, or several PCs linked together. • Data, radar & sound replay (AMI-Geonav program) • AIS replay (AIS is optional, by ESL program) Once installed and set up on your PC this gives the full replay facility. The software has to be purchased as an optional extra. Ships do not have to carry it.

9.

Can we connect the ship’s computer network, or a voyage management system, to the VDR via the LAN?

10. What about replay?

11. We want to replay the data on one computer.

OK. You can. This is fine for on-board checks. It will be awkward to see it all in real time as you really need separate screens for • instrumentation, rudder, alarms etc • Chart – plotting screen • Radar picture • AIS data For a serious investigation you can use a computer with 2 screens. Or, 2 computers giving 4 screens. (Plus the audio replay)

12. How do we get copies of the saved data from the s-VDR?

• • •

Connect your portable computer to the s-VDR with a standard RJ45 ethernet network cable. We will supply companion software to explore, select the files you need by date and time and copy them onto your computer. During this process the s-VDR recording is not interrupted. This is only required after a serious incident when the capsule is not connected to a MEU, or for test purposes. Install the capsule download program onto a computer and run it. Connect the capsule to power and via a local area network cable to the computer Follow the published instructions. The program will copy the data in the capsule onto the laptop’s hard disk.

13. How do we get data out of the memory capsule?

• • • • •

14. Can it connect to a float-free EPIRB capsule?

Not yet. I am in touch with ACR and McMurdo, but none have yet been able to provide one so that we can program the MEU. We are hoping it will be come soon. Jotron made an offer about using their capsule but it was not advantageous to us. Robin tells me that the EPIRB makers can not conquer the problem of salt water getting to the electrical connections.

15. About the “5 incidents save”. Will these

No.

incidents be recorded in the capsule?

The incidents are only saved in the MEU. The number of incidents which can be saved depend on the file size, but would be typically a minimum of 5, but it depends on file size

16. You say the MEU can store LAST 24 hours data (plus 5 or more 12 hour incidents.) Is it possible to make it longer?

The MEU will usually save more than the last 24 hours, mostly dependant on the size of the radar picture. The s-VDR is purposely designed NOT to save huge quantities of data on its hard disk. Storage is minimised to simplify the software internally and therefore make the s-VDR very reliable. NO. The design is fixed to handle that a certain sizes of data files for technical reasons. It is not a matter of cost. Only by pressing the “save” button every 12 hours to save use the save incident function, and assuming the file sizes did not exceed the “J-partition” total. The s-VDR is not intended to store long voyage data at all.

17. Is it possible to make it (The 24 hours data) longer than 24 hours by using a bigger size hard disk? 18. Can we say the s-VDR can store up to 84 hours, about 3.5 days in total if no incident happens.

19. Comment from the designer

Thank you Kenny at AMI Singapore for the feedback. I will always do my best to answer questions and make the answers available for AMI’s clients. I do not want to reveal to competitors the design principles which make this s-VDR so good. I have tried to SIMPLIFY the s-VDR, and make it meet the requirements of the s-VDR rules. I have NOT tried to make it do all sorts of fancy extras that it does not need to do. The amount of data that can be stored within the MEU is mainly dependant on the size of the radar image files.

20. It seems to take a very long time to download the data from the L3 capsule.

• • •

It can take more than 4 hours to download the data because of the protocol and comms speed used by L3’s capsule. Downloading is faster with the latest L3 capsules which have 10 times the comms speed, and with a fast computer. Let’s be practical. Does it really matter if it takes hours to get the data from the capsule? When is data downloaded from the capsule? Recovery of data after the ship has had an accident o In a lab ashore o On board when the MEU is destroyed o ( Recovery of data to prove the capsule is OK at a survey. o Why not do what DNV require for surveys, take samples to prove it has been recording the last 12 hours o A copy of the capsule’s data is always available for fast access in the MEU)

• 1.

2.

21. “2.5 hours” of 2nd line should be replaced “3.0 hours”. Because some type approved capsule take 3 hours for fullsize downloading. Consider the actual down loading time in the market. Request from Japan to the s-VDR working group. 22. Doesn’t the MEU have a copy of the capsule data?

Answer from the s-VDR working group. Not agreed The requirement is for downloading from the memory that contains the "saved" data, not for the data stored in the protective capsule. Please be also reminded, that this requirement does come into force for equipment installed on or after June 1, 2008, and is therefore not necessarily relevant for existing memory/recording solutions YES! • The MEU always has the same data in it as the capsule, and this can be copied from the MEU quickly if you ever need a copy of what is in the capsule.

•

Hold the SAVE INCIDENT button to save the last 12 hours as an incident.

23. When saving data (4.5.1) is in the COTS interface (e.g. PCMCIA card, USB memory, and compact flash memory etc.), the COTS interface should be used as an alternative interface for down loading. This method is very fast, it takes for few minutes to transfer the recorded VDR data to the investigator’s protable computer. Request from Japan to the s-VDR working group. 24. COMMENT: See below for the calculation of capsule memory size required for certain size radar screens.

Reply from the s-VDR working group. Not agreed This was discussed at length, resulting in the conclusion that an "interface" which must be detached from the equipment in order to communicate with an interface of the investigator's portable computer, is not an acceptable solution

RADAR INTERFACING
25. A radar’s RGB output does not produce a picture on the s-VDR. Some radars claim to have an RGB output, some Decca radars for instance, but they do not conform to the list of standards the s-VDR specification calls for. To prove any radar’s output is good, first connect it to a standard PC monitor. If you can see the radar picture the s-VDR will record it. If not, then it can not be recorded unless a special interface is available from the radar manufacturer, and the owner pays for it. For an s-VDR the alternative is to record AIS data. For a VDR it may mean installing a new radar. 26. “But Mike said it would record that radar so you MUST DO IT.” We can only do what is possible. If the radar is at fault we can not record it. It must have a proper RGB output. In some case the ship will have to buy a new radar. If no RGB interface is available from the radar makers, then the sVDR can not be connected. 27. The classification society demand we record radar on the s-VDR, but the radar has no RGB output. 28. What happens if the radar is turned off? Is there an alarm? 29. When there was a monitor connected to the s-VDR during installation the radar picture looked better on the VDR than on the radar itself. 30. Is it possible to record two radars? Buy a new radar. Or change your society. Radar-off is a normal condition so there is no alarm. The “radar acq” led will not flash. A small picture saying “no radar video” will be recorded every 15 seconds. Your radar screen is worn out, or else the monitor has much better resolution than the radar screen. Notice that this means the s-VDR is not necessarily recording exactly what the navigator sees on the screen. It is not an option offered. For development puroposes I have tried it and it works, but it is not yet an option that has been brought in to use, and is not sold with the s-VDR. It would only be possible with 2 smaller sized radars because of the file sizes. I predict people would then want to do it with big radars. We do not have a live replay program for 2 radars. So, it is not an option.

31. Why is the maximum size radar screen 1600 x 1200?

1. It is a matter of the file size produced by the RAI. Bigger screens produce bigger image files, which would be too great for the system. That includes the time taken to send the data to the capsule. 2. IEC 61996 only requires screen size up to 1280 x 1024 3. 4. 5. 6. 7. The VDR I am using saves simulated radar picture of 1024 x 768 as JPG files of 0.5 GB every 15 seconds. By extrapolation I calculate these to be the storage requirements: 1024 x 768 screen uses 2.2 GB for 12 hours 1280 x 1024 screen uses 3.4 GB for 12 hours data o This is the biggest size screen that IEC 61996 calls for 1600 x 1200 would require 4.3 GB for 12 hours data. Check the capsule size is sufficient. If you have any other information to verify this please call me and talk it over. These figures are very approximate.

32. Can we use the VR2272 external RAI? 33. To pass the radar VGA cable through the gland plate needs too big a hole. 34. What about radars with non standard VDA output such as sync-on-green?

No Take off the gland plate, or one of the side plates and cut a slot in the edge to fit the cable. Seal it afterwards if you want to preserve the seal. Soon there will be a new optional RAI, at an extra cost. It will connect to RGB Hsync & Vsync (5 wire) and handle interlaced signals and sync-on-green.

ECHO SOUNDER INTERFACING
35. “But Mike said it would record the echo sounder” If the echo sounder on the ship has no data output, and no output for a remote display, we can not possibly interface it. So, owners sometimes have to fit new echo sounders. 36. Can’t we connect up to some test points inside the echo sounder? That is an unauthorised modification. My advice is that you must not carry out any unauthorised modification. If no COTS interface is available, then it can not be connected. 37. We have tried connecting the KW950E to the echo sounder’s output but “it does not work” This turned out to be the 500 volt 50 kHz signal to the transducer. The KW950E does not connect there. It can connect to typically 12v DC pulses which are output for driving a remote display. The KW950E can convert some proprietary data. S-VDRs do not have to connect to the echo sounder.

INTERFACING VARIOUS EQUIPMENT
38. The wind instrument has a synchro output, can that be interfaced? YES. You need a KW910. It is probably cheaper to buy a new weather instrument with NMEA 0183 output. 39. The classification society demand we record revs and rudder angle 40. We want to record AIS and other interface data. 41. Can you confirm the sentences you use That’s an “optional extra”. I guess you have to do what they say. AMI probably have the extra interfaces you need. No problem, use the data combiners and interfaces feeding into the s-VDR expansion port. (Set the port to 57.6 Kbaud) It is ZDA and / or RMC to update the clock, the reason being that the

to update time, and date?

GGA sentence doesn't include the date, just the time. This ensures that the clock is correctly updated with the day, month and year.

ALARMS
42. Is there an alarm if the GPS fails? Not in the last batch of s-VDR. You can easily see data input activity on the LEDs. The s-VDR is not designed to be an alarm unit. However, it would be unusual for GPS data to stop for a long time, and it is used at intervals to update VDR time so the next update to the MEU will give an alarm if GPS data fails for 1 hour. 43. Audible alarms seem very quiet. Yes, they are quiet. Alarms specified by IEC 60945 are 75 to 85 dbA but the 61996 VDR specification says the VDR alarm should be 55 to 65 dbA.. This is because VDR alarms are not considered as important as main alarms. OK Marie. When the spec calls for a low level audio alarm should not the visual alarm also be at a low level? No. The display of the KW950T has been transferred to the MEU. The audible and visual alarm has been transferred to the low cost M3 remote alarm unit.

44. The red alarm LED does not seem bright enough to me. 45. Can we use the KW950T remote alarm unit?

AUDIO SYTEM
46. You must have a microphone at EVERY work-station, radar, chart table, bridge wing etc. Not true! The s-VDR standard document IEC 61996 says…. “ One or more microphones positioned on the bridge shall be placed, such that conversation at or near the conning stations, radar displays, chart tables etc may be adequately recorded. As far as is practicable, the positioning of microphones shall also capture the input and output of intercom, public address systems and the audible alarms on the bridge (bridge mounted equipment) “ This really does mean 1, 2 or 3 microphones can be quite sufficient. In fact the fewer you have the better will be the quality of the recording. 47. Microphones were picking up music from a fairground ashore. Are they too sensitive? Mics are self adjusting to suit the sound level on the bridge. So, if it is very quiet it will record low level sounds. But, as soon as someone starts speaking it will adjust to record the voice perfectly. This means it is NOT necessary to have many microphones on the bridge. Indeed it is preferable to have very few, then sound will be clearer. 48. How are the microphones tested? • • • • • • • • There are analog and digital signal processors. Audio testing of the microphones is continuous Audio test of the interface is 7 minutes after switch-on or 7 minutes after pressing the mic-test button. Every 11 hours 45 minutes the test is repeated. The LCD shows results for all channels. When the next issue of EP software is installed the LCD shows audio activity as a % of max Each microphone has an activity LED inside.

NOTE: You can plug in a 32 ohm headphone to the green audio socket and monitor the audio. 49. The microphones MUST have an active • Where does it say that in IEC 61996?

sounding BEEP test.

• • • • •

Question to you: Why do you need an active beep test if the 2272B is clever enough to do without it? Actually there IS an active sounding BEEP test the 2272B can use if it is ever required. If the ship’s bridge is so silent that in 11.75 hours there is no sound whatever, then the MEU and remote alarm will give a short beep to activate the microphones. There is also provision for fitting an external beeper to a mic. If you have better idea please call me and explain it so I can put it into action. Feedback is what I WANT! I do not think blue-tack will stop the microphone working. If the microphones are sabotaged the MEU will detect this and raise an alarm. I have no intention of increasing the cost of this simplified VDR to prevent possible sabotage. IEC 1996 does not require it, so it is not included. I suggest masters routinely check their VDR is in good working order, perhaps once a week. However, if YOU can sell the owner additional rat-guards and protective measures, because they fear sabotage, please do so.

50. The microphones should be protected because people put “blue-tack” on them to stop it working.

• • • • •

51. One our Danish customers have asked if it is possible to password protect the audio files, as the Danish Seamen Union are threatening strike action if the owners are allowed free access to them! Robin

The immediate answer from me is no. BUT tell the Danish seamen, their request is not allowed by the VDR specification. The comment applies to ALL VDRs not just ours, so I suggest they put their representations immediately to the s-VDR working group who are still formulating the new standard. Here are some contacts. Mike Rambaut - CIRM" <mr@cirm.org>; Hubertus F. Wentzell" <hubertus.f@wentzell.de> Andrew Not daisychained Russel, but It is possible to add more microphones using a combiner interface as an optional extra.

52. I may have picked it up wrong, but my understanding was that the audio unit could be daisy chained with another identical external unit to support additional microphones. No ??? Russel 53. Robin, why are you asking if we can connect more microphones? Andrew

Chinese shipyards want to put a microphone at every work station. So, you have 3 mics spaced at 1 metre intervals over the wheel, radar, and ecdis. I KNOW this is not required, but that’s what they want. Robin. The customer is always right. Don’t forget to charge for it. Andrew

LEDS AND DISPLAY
54. The front panel LEDS look too bright for a dark ship’s bridge. The s-VDR has a light sensor on it and will automatically dim the LEDS when it is dark. (Except for the status LED which only comes on if there is a problem) There is an internal switch so you can have them full on all the time if you want to put the MEU in a cupboard. Red LEDs appear brighter than the green ones. 55. Would it not be better to have the front panel LEDS green, except for the alarm LED? 56. What about a lamp-test to show the LEDS are working? YES! Only the first prototypes have all red. All production s-VDRs front panels have 15 green LEDs. The two red LEDs only come on if there is a problem. Half of the LEDS flash routinely or are on continuously or give a flash at start up.

9 LEDS flash when external data comes in. It will be possible to get 8 of them to give a flash on switch-on in the future. LEDs are extremely reliable in service, in fact I do not know ever of a case of one failing in our equipment. If you hold the accept-alarm button one of the otherwise-hidden screens puts on all of the LCD pixels. 57. There should be a dimmer control The s-VDR detects darkness and reduces the brilliance of the LEDs th to 1/8 of the daytime level. If they are still too bright fit some screen inside the front door. Really. Reverse the front panel, that will hide most of them. Are these the same people who sabotage the microphones? FA = figure awaited, nothing there yet, used at start up. FF = figure failed to arrive, after a time-out.

58. People wont like those flashing leds and will put tape over them. 59. What does “FA” mean on the display?

VHF RADIO INTERFACING
60. The VHF has no direct output of transmit and receive audio, so how can I make the direct connection to it. You can not connect. The VDR spec 61996 says • • “The audio connection with the designated VHF equipment shall be in accordance with the requirements of IEC 61097-7.” Unfortunately IEC 61097-7 says nothing about the connection. I have not pursued the matter with the IEC working group on the basis that it the spec was changed it would will help competitors.

61. Can’t I modify the handset or solder wires inside to get at the audio?

NO. That is an unauthorised modification. Please do not carry out any unauthorised modification to ANY piece of ship’s equipment. Just like the radar, if no COTS interface is available, then it can not be connected.

62. What about the AMI RT2049 interface for the Sailor RT2048?

The AMI 2049 interface intercepts the handset cable plug and socket with a direct connection in a very neat way. The AMI 2049 interface is Type Approved. This interface is not part of the VDR, it is an extra.

63. What can be done if there is no direct audio output from the vhf?

Chose another VHF, or else the owner will have to fit a new VHF. This seems ridiculous. The practical thing to do is put a microphone close the VHF operating position. OR even FIX it to the VHF so it is physically if not electrically connected. If the radio is simplex only with a loudspeaker that can not be switched off then both transmit and receive audio will always be recorded. VDRs are no longer new so there must be VHF radios made with an audio output for use with VDRs. Some radios have a “line” output, especially those used for GMDSS.

64. But Broadgate used a scanner connected to the VDR. 65. To THRANE & THRANE To: Thinus Svendsen (TS) Subject: VHFs which have an output of transmit and receive audio

Not allowed by the rules, it must be a designated VHF radio telephone. Good morning Andrew We have several VHF's in our portfolio that suits your need. The RT5022 (simplex) and RT5020 (Duplex) can interface directly to

Good morning I am trying to find VHFs which have an output of transmit and receive audio to go to a VDR. That is, a line-level output. Alternatively might you have an interface that intercepts the handset connection and output tx/rx audio? Thanks Andrew Fairgrieve

a VDR. The RT5022/RT5020 are GMDSS VHF's with DSC class A, and were launched last year. The SAILOR RT4822/SKANTI VHF 1000 DSC (simplex) and SAILOR RT4722/SKANTI VHF 1100 DSC (Duplex) can interface via the SAILOR H4996 VDR Interface box. These VHF's were launched in 1997 and are fitted in a large number of SOLAS GMDSS installations. The RT2048 (simplex) can be interfaced to VDR via the SAILOR H2049 VDR Interface box. Please be aware that if you connect anything to a GMDSS radio, it has to be type approved together with the VHF. If not the vessel may experience that the surveyor see this as an illegal installation and stop the vessel. All our distributors around the world are trained in installing these VHF's and the VDR boxes, even though it is quite simple. If you need support in the connection to one of the above VHF's, I suggest that you contact one of our local distributors. They will be able to assist you. Do you develop your own VDR's? Best regards Henrik Fyhn Market Manager Radiocom T + 45 39 55 86 10 M +45 20 72 64 00 E hfy@thrane.com

66. To SEA INC, USA To: sales@sea-dmi.com Subject: VHFs which have an output of transmit and receive audio Good morning I am trying to find VHFs which have an output of transmit and receive audio to go to a VDR. That is, a line-level output. Alternatively might you have an interface that intercepts the handset connection and output tx/rx audio? Thanks Andrew Fairgrieve

Andrew: Currently our standard VHF radios do not have the line level output for VDR. I have built and installed a small assembly that can be added to these radios to provide the required line level output (SEA157 and SEA7157) for some existing installations that were being upgraded to include VDRs. We are in the planning stages for redesigning our VHF products and these next generation radios will have the line level output included in the standard configuration. So if you would like to recommend our current products please mention that the line level output is an option and should be requested when making inquiries or placing an order. Your question regarding the handset connection the biggest issue is that the receiver audio is controlled by the volume control which means you only get your nominal line level at one volume setting. With the internal interface modification the receiver audio is sampled before the volume control. I hope this answers your questions, if not please let me know. Gary L. Kison Staff Engineer SEA, Inc. 425-771-2182 x145 (From this reply I conclude SEA radios do not yet come with an output suitable for VDR.)

67. To: L3 / ROSS To Meloche, Tom @ AR Subject: Ross DSC500-Pro-M VHF Hello Tom I am trying to find VHFs which have a transmit & receive audio output for a direct connection with VDRs. So we can reccommend them. Is the optional output easily available and is it a single line-output?

Hello Andrew, It's nice to hear from you. I hope you've been well. We make a interface box that allows our DSC500 to be routed to a recording device. I've attached some information about it. If you have any more questions, just ask. Best Regards, Tom Meloche

Best wishes Andrew Fairgrieve

Technical Manager L-3 Communications Marine Systems 6000 Fruitville Road Sarasota, FL 34232 (PDF data sheet available from L3, who own Ross Engineering. You can buy the L3 interface for connection to VDR.)

68. TO ICOM: Good morning I am trying to find VHFs which have an output of transmit and receive audio to go to a VDR. That is, a line-level output. Alternatively might you have an interface that intercepts the handset connection and output tx/rx audio? BR Andrew

Andrew Thankl you for your email. Our M602 VHF Marine tranceiver can be modified to accept a handset...........this mod would allow you access to the reciever audio and transmit audio. This is the only product we have that allows access to these features. Gerd Jerochim Technical Support Representative ICOM America, Inc. 2380 116th Ave. NE Bellevue, WA 98004 Ph. (425) 454-7619 Fax (425) 637-8417 www.icomamerica.com (I asked for the official approved instruction for the mod.) YES, PLEASE SEE ATTACHED. We recommend it be done by icom or a authorized Icom marine service center. Gerd Jerochim Technical Support Representative (The modification sent me did not provide a line-output, therefore ICOM VHFs can not be connected to VDRs in an official approved way.)

69. To: JRC Japan Good morning I am trying to find VHFs which have an output of transmit and receive audio to go to a VDR. That is, a line-level output. Alternatively might you have an interface that intercepts the handset connection and output tx/rx audio? BR Andrew

Dear Sirs, JRC is manufacturer of complete navigation and communication equipment. Also VDR/S-VDR products are included. Our VHF products interface seamless to our VDR/S-VDR products and do not need interfacing. We do not devellop or produce interface systems for other manufacturers. We trust this information suits your requirement for the moment. Yours sincerely, M. van Uggelen High Seas Sales Japan Radio Co. Ltd. - Amsterdam Branch Tel. +31 (0)20 6580750 Direct +31 (0)20 6580757 GSM +31 (0)6 54795446 (It looks like there may be a way to interface JRC VHFs but JRC are not going to tell me. Andrew.)

70. Robin, can you cannect to Furuno VHFs?

We have connected to the Furuno FM 8800. It has a line output of transmit and receive audio. Robin (Confirmed in its spec the audio for VDR is in the JB IF-8810.) No info found about the FM8500.

DATA OUTPUT FROM THE s-VDR DATA RECORDED BY THE s-VDR
71. The VDR has gathered-in all this data, so lets feed it to the ECDIS. What is the format of the data output of the VDR? FORMAT AND CONNECTION • NMEA 0183, single 5 volt level at 38400 baud • Data A or + = SK2 pin 2. Ground = SK2 pin 3 • This output is provided for test purposes to drive a computer’s RS232 port via a short cable. • It is used during commissioning, test and survey. • Pin 1 is +5v to allow connection to a bluetooth transmitter. • The next build of s-VDRs make this output an official high speed NMEA port with A, B and C connections, especially for feeding to an ECDIS.

DATA OUTPUT • Data out is a repeat of the 4800 baud data input, on a first-in, first-out basis • The data is filtered to reduce the amount of data recorded • • PLUS a $VRALR message giving the alarm state of the VDR every 256 seconds PLUS, certain proprietary messages beginning with $PADI or $PAMIV. We do not publish their meaning & they are of no value to the outside world. PLUS certain $VRTXT messages which are used for test and development purposes. We do not publish a list of these messages and may remove or add to them at any time. The data you see being output is being recorded by the VDR.

•

•

THE DATA FILTER has the following functions to minimise the data recorded to the essentials required for a VDR • • • • GPS port passes GGA, VTG, ZDA, RMB, RMC, DTM GPS port filters out all proprietary messages GPS port does not pass other messages because they are not required as part of the VDR or s-VDR specification Heading input port filters the data to pass 1 per second the message HEHDT or HEHDG or HEHDM o This is because many gyros send continuously, when all that is needed for a VDR is one per second. Depth input port passes 1 per second SDDBT or SDDPT o Again this is because some echo sounders have been seen to send at 10 times a second. Speed input port filters the data to pass o Headers VB, VD, II, o Sentences VBW and VHW The data filter characteristics are embedded and can not be changed. For test purposes the filter may be switched out on the CDP board, but use in that condition may lead to a dataoverload alarm If you have any requests to change the filtering please call or email and I might be able to accommodate you in the next build of s-VDRs.

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The AIS or expansion input is not output

72. Why has this page got so much space below?

I do not know.

POWER SUPPLY
73. Can we have a mains on off switch on the AC-DC power unit? I have considered this very carefully and designed it without a switch for a very important reason, safety. What I recommend is that you isolate the AC at an external circuit breaker. If there was an on/off switch on the power unit it would mean that mains power was still present inside the box at all times. Therefore, when connecting up or changing the battery there would be risk of fingers or wires coming into contact with the power. There are further benefits. Because the s-VDR must run continuously its power is less likely to be switched off. Having no switch is a simplification and lowers cost. 74. Will you paint the power unit enclosure black in future please? Certainly. This increases cost of course due to the labour to block the tapped holes, powder coating, and transport. The enclosure is “clear passivated” which is compliant with the EC “restriction of hazardous substances, ROHS,” directive. Other colours such as yellow and black do not comply. 75. Will you fit a lens for the internal LED and extend it out to the front panel? No, it’s an unnecessary complication because the MEU already acts as both the status indicator and alarm for the power supply. If you do not like the small hole through which you can see the LED please cover it with a label. 76. I see the s-VDR says STANDBY – ON. How do we switch OFF? If you are going to switch the s-VDR to standby for long periods then • 1. Switch off the mains isolator & • 2. Disconnect one battery lead to avoid total discharge

MANUFACTURING ISSUES 77. There is an “unknown” encapsulated area on the main board. What is it?

• • • • •

1. The s-VDR’s protection system or dongle 2. The DSP circuits for the audio testing system 3. Part of the NMEA 0183 data processing circuits 4. On the first prototype s-VDRs it was made as a plug-in module, but now it is permanent on the main board. The circuits are encapsulated to prevent direct copying, or the stealing of the methods used to do the functions above. Years of work have gone into the design of these circuits and I have no intention of revealing to competitors exactly how it is done. This is in line with many manufacturers (such as Furuno for example) who do not publish full schematics. This caution comes after at least 3 very blatent copies of some of my designs have been discovered. Many companies use dongles to protect their software.

• • 78. The control display board says 12 mm spacers to be fitted, but 10 mm are used. 79. Wouldn’t the hard disk drive be more reliable if it was mounted horizontally? Advice about changing the HDD…

Correct, and 12 will be changed to 10 on the next issue.

It IS horizontal, when the s-VDR is mounted on the bulkead. The HDD manufacturers guarantee the same performance and life for their HDDs used in ANY orientation. The hard disk drive is easy to plug-in incorrectly unless you do it like this. • Undo the 4 fixing spacers o which are easier to handle than screws. • Bring out the HDD with cable attached. • Replace or first fit the HDD.

• • • •

The black and red wires are closest to the edge of the HDD Check the connector is firmly down Remember to fit the in-line black and red power connector Fit the HDD back in the s-VDR Never try to plug-in with the HDD mounted on the wall of the s-VDR o

80. Can you use a solid state disk drive?

Yes, if you can accept the increased cost. Solid state disks are currently advertised at about $500, rather than $50. It is usual to supply a spare fully programmed HDD with each s-VDR installation.

81. The monitor connection is a bit tight to get in, can’t you raise the board? 82. Why do you call the computer an EP?

The next metalwork made will give more space for fat monitor cables. It is the embedded processor. People got in the habit of calling the computer in the original VDR a PC, but there was no Personal Computer, monitor and keyboard in it at all. Yes, of course it does. All our manufacturing complies. Unfortunately this increases the price of the s-VDR. Here is an example. A 4-pin connector for the PSU used to cost £0.34. The ROHS version is now £0.55. Apply that across the whole production. Use a USB extention lead.

83. Does the s-VDR comply with the EC Restriction on Hazardous Substances ROHS directive?

84. There is not enough room to get a USB memory stick in, so how can we update? 85. We have lost the keys, where can I get more?

We supply 2 keys fixed to each CDP board, so they should be there when the s-VDR arrives. The keys are RS 182 556

ROUTINE MAINTENANCE
86. Please could you assist me by making suggestions on what parts would be required for this system over a period of about ten years? Sally Here are my suggestions Sally o Replace the EP fan every 4 years. The s-VDR will work perfectly without the fan. o The AC-DC power unit battery need not be replaced routinely. It will probably last 10 years. Test it yearly to see that it will run the s-VDR for 2.5 hours, and if so it is OK for another year. o The BIOS battery will also last many years. Replace every 4 years, along with the fan. o Replacement batteries should be purchased as new when required, not kept on board. o Any other suggestions anybody? This is not a full list. I have just updated the embedded software for the CDP. If anybody wants it to update their s-VDR it can be downloaded from the web. Particular thanks to Kenny in Singapore, Ollie North, Russel Morton, Andy Midgely, Peter Goddard, Robin Grigg, Marie, and Mike Woods.

87. Comment:

THANKS From Andrew Fairgrieve


				
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Description: VOYAGE DATA RECORDER Questions & answers 2 GENERAL ISSUES DATA