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      Abbreviated rules   07/28/2017

      Underdawg did an excellent job of explaining the rules.  Here's the simplified version: Don't insinuate Pedo.  Warning and or timeout for a first offense.  PermaFlick for any subsequent offenses Don't out members.  See above for penalties.  Caveat:  if you have ever used your own real name or personal information here on the forums since, like, ever - it doesn't count and you are fair game. If you see spam posts, report it to the mods.  We do not hang out in every thread 24/7 If you see any of the above, report it to the mods by hitting the Report button in the offending post.   We do not take action for foul language, off-subject content, or abusive behavior unless it escalates to persistent stalking.  There may be times that we might warn someone or flick someone for something particularly egregious.  There is no standard, we will know it when we see it.  If you continually report things that do not fall into rules #1 or 2 above, you may very well get a timeout yourself for annoying the Mods with repeated whining.  Use your best judgement. Warnings, timeouts, suspensions and flicks are arbitrary and capricious.  Deal with it.  Welcome to anarchy.   If you are a newbie, there are unwritten rules to adhere to.  They will be explained to you soon enough.  

littlechay

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littlechay last won the day on April 7

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About littlechay

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    http://www.tweedsworld.com

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  • Location
    Christchurch
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    sailing, photography, climbing, mountaineering, skiing, boat building, electronics, communications.

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  1. VOR Leg 7 Auckland to Itajai

    Absolutely right on all counts. If you get outside of that 5nM design range then reception will be patchy but ranges over 25nM, to masthead antennas, have been achieved in testing in moderate to rough sea conditions - (Source - a chap from RnD at McMurdo). The difficulty with getting more power out of the AIS SART is the battery power v size. A larger power amplifier IC isn't going to increase the size much but transmitting 5W over 1W is going to make a significant difference. Depends how long you need it to transmit for. Arguable an AIS SART doesn't need to transmit for 24 hours or 48 Hours like a satellite EPIRB so what is acceptable... 4 Hours, 6 Hours.. 12 Hours..... It aint easy. Oh well next leg starts soon
  2. VOR Leg 7 Auckland to Itajai

    Well both AIS standards have always allowed SOTDMA and some have been around for a while. The advance in what is on the market is that some of the newer Class B ones seems to Tx 5W so I would think that the splitters would be fine as they are already designed to take up to circa 50W on the VHF set side. The higher reporting rate is probably more important in rough sea than the extra 2W Tx power. I say that because the 3W link budget is more than adequate for line of sight for a person in the water to a yacht antenna whether it is on the top of the mast at 30m or the comms tower. at 3 or 4m. What is important is line of sight and the higher update rate of a SART will help to get a signal through whilst both are in LOS i.e. in top of waves. However all that said and as I touched on, when we are talking about AIS SARTS ; they are already transmitting at a higher update rate. To save me paraphrasing something here is the relevant Wikipedia entry. " Search and rescue transceiver (SART) Specialist AIS device created as an emergency distress beacon which operates using pre-announce time-division multiple-access (PATDMA), or sometimes called a "modified SOTDMA". The device randomly selects a slot to transmit and will transmit a burst of eight messages per minute to maximize the probability of successful transmission. A SART is required to transmit up to a maximum of five miles and transmits a special message format recognised by other AIS devices. The device is designed for periodic use and only in emergencies due to its PATDMA-type operation which places stress on the slot map."
  3. VOR Leg 7 Auckland to Itajai

    Nah I have put AIS next to FB500 and 250s before. The rig has to be properly designed and interference mitigation planned for but definitely doable. I would think anything on the rails is going to get knocked off. A bit more height is always good too. A splitter is only required if they share the same antenna. But yes agreed that they would probably only want one antenna.
  4. VOR Leg 7 Auckland to Itajai

    I wouldn't use a rail mount or a splitter. They have a comms mast on the back of the boat. Spare antennas should be installed there. I would reluctantly use a splitter; better to use a good quality coaxial switch with a big knob on it labelled "Emergency antenna". Manual but more reliable. Better still a fully redundant AIS/VHF radio system on that antenna. In a once design the weight isn't an issue and in any case an AIS transceiver weight what? 500g?
  5. VOR Leg 7 Auckland to Itajai

    I have it on my boat... runs on a Raspberry PI home mode plotter system though Big red button
  6. VOR Leg 7 Auckland to Itajai

    This is a good way to do it - momentary push drops a mark (to mark a whale sighting for for example) and long press for MOB.
  7. VOR Leg 7 Auckland to Itajai

    Yep - and it was mentioned in the discussions on the MOB incident at the time.
  8. VOR Leg 7 Auckland to Itajai

    You could be onto something with that. Buenos Aires used to be a stopover in the old beer race up until the war when it was moved to Punta del Este which is in no way equipped to deal with a stopover. BA could be a good stopover ..... and the race up the channel to the YCA would be entertaining. Argentina have probably made representations on the use of the name, they usually do; which is the pretty much the only reason we make representations. Argentina recently threatened to refuse filming right to National Geographic because they used the term Falkland Islands.
  9. VOR Leg 7 Auckland to Itajai

    I never commented on his sailing skills. But obviously doesn't get the politics of the Falklands at all. Or perhaps he does and he is making a statement in which case he should leave politics to the politicians.. He said "Las Malvinas" with some emphasis like he was trying to make a point. As Jack said very much like leaving an unflushed turd! Maybe I am being oversensitive but my life has been made quite difficult by the neigbours from hell.
  10. VOR Leg 7 Auckland to Itajai

    I wondered that or more likely despite the time he spent in the islands he just doesn't get the sensitivity of the issue.
  11. VOR Leg 7 Auckland to Itajai

    All the help that they got in the Falklands from Falkland Islanders and Foxall keeps using the M word in this movie clip and in print. The man in a CUNT.
  12. Next VOR on IMOCAs?

    True comparison. I know several people who use Watt & Sea units on cruising boats and they are happy enough... 300W & 600W versions (there is now a pod version but with the same fragile prop [nightmare]). Of course shaft alternators are nothing new. Run a big enough water wheel and you can generate any amount of power but you have to overcome the drag somehow; or everybody uses the same device and then the competition comes down to power management - manage your power better and use the generator less = go faster.
  13. Next VOR on IMOCAs?

    RIght! The most bang for the buck, energywise, is to use diesel as the primary fuel source. Unless their boats are build using no electricity that is traceable back to carbon fuels at all then they are not on a carbon free footprint. The cleanest way to sail around world and remain carbon neutral would be in a wooden boat with wooden nails, flax, hemp or cotton ropes and sails etc. etc... that could be done carbon neutral - any other way is BS.
  14. Next VOR on IMOCAs?

    The props on them are pretty fragile and I imagine if using HGs was compulsory there would be a lot of prop failures in light winds with long and lengthy struggles to change them.
  15. Next VOR on IMOCAs?

    Yea he has done some cool stuff. I suspect the control and media rights is part of it. Although there is no way to get the media off the boat during the race (by technology means) except the media drop points where film will be collected by the organisation - It's all a bit "big brother" for me. The cost of film v digital photography does not stand up as film is more expensive in every way, to buy, to carry, to store, to develop, and to distribute. To distribute it will all have to be digitised anyway ! I think that it should be up to the competitors how they record their trip. I'm not too sure what to make of the one-design Joshua replica category for the next installment. I know he thinks it is the ideal boat, but not even Moitesier thought that . I suspect that buy ordering and building several it is a way to get his own hull cheaper or for nothing if he sells enough ... fair enough too.