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":A 2h18 heure française, le team PRB a été informé du sauvetage de Kevin Escoffier par Jean Le Cam. " Kevin has been rescued.  

Give it a rest chaps. HB was another attempt at evolution, and they should be applauded for spending a fuck ton of money to do so. If you want to try and be innovative you run the risk of breakages al

VG sailors at sea in the rough A translation: JLC: Damien can you receive me ? DS: Yes Jean I can (garbled)... I don't think you're receiving me that well but I receive you very well. JL

Posted Images

26 minutes ago, ivansh said:

So does tipandshaft mean something else in French or is that just an excellent choice of website name?

Hard to take? (sorry, kinda)

Excellent name for an excellent site. My goto site for ocean racing news when I can't read here, mostly because they ask good questions of the key people and don't rely on "how do you feel?' sentimentality. IIRC, a few years ago Leov?, or another anarchist here recommended signing up for their newsletter. Their translation page, linked in the newsletter, makes it easy to follow for a non-native French reader. 

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That fishing fleet is unfortunate for AT. I had assumed he would sort of keep the same heading for another 36 hours so he had slightly better pressure then the boats to the east, and then turn ever so slowly east and aim for the patch of wind that will hopefully be there as predicted and get him still in first place around to the cape. Now he has to go east earlier, it seems. 

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1 hour ago, Rafael said:

FishingFleetHBCourse3.jpg.d6f73febbb82c98a02b08b97f8f6e436.jpg

 

** fark now looks like Alex has decided to clear it to the East (img3) probably less expensive...

Nice update. Thank you. 

Question now is?

Is he hardening up and 'cashing in' on what he has in the 'bank' BUT will slow OR still 200nm short of Salvador the breeze has already backed more than forecast and bringing him east??

I'm guessing a bit of both wanting to put himself between low and the others 

10 hours ago, jack_sparrow said:

AT might be kissed on the dick here.

He has already hardened up slightly stopping the lateral bleed but still motoring with COG just west of south. It will be less than 180 soon.

 

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41 minutes ago, Rafael said:

Looks like a change in the lead for today!... the blue young blood has some legs!...

as so Dalin who marked 92Nm the last 4hr period and 505.5Nm in 24hrs (!)

LinkedOut.thumb.jpg.3a66963769d8d5f4a91baec76168972f.jpgApivia.thumb.jpg.0d9d4dc3a7154367cc82a2b03a0db7d0.jpg

AlexSurprise.jpg.2f1763e3663edbcca05539df9bcd8348.jpg

92Nm the last 4hrs and 505.5Nm in 24hrs (!) WTF!!

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30 minutes ago, jack_sparrow said:

Nice update. Thank you. 

Question now is?

Is he hardening up and 'cashing in' on what he has in the 'bank' BUT will slow OR still 300nm short of Salvador the breeze is already backed more than forecast and bringing him east??

I'm guessing a bit of both 

 

Let's see how he works it out... not a clue of what he will do (seems like now he is going strait up to the fiesta)..., but for sure looking to the last sched, the temperature of his melon has uprised maybe near to a boiling point (has he a sensor for that ?...) :D;)

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You guys realize that 100nm is nothing in this race, right? The skippers are sailing their own race, with their own routing and macro-level decisions which play out over weeks, not between tracker updates. It seems a bit pointless to talk about boats gaining or losing 20nm, or that someone behind is going 1 knot faster. It's chess, and the skippers are thinking 10 moves ahead, not about if someone is closer to rhumb than they are.

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43 minutes ago, ivansh said:

You guys realize that 100nm is nothing in this race, right?

NOW and just ahead probably the most important part of the entire race course, more so than the two ITCZ crossings and exit away from the Horn. 

100 mile or even less can be the difference for getting to the 'station' to catch the eastward Express OR missing it and having to wait for the next one. 

That 100nm can then suddenly become a 1,000nm lead or a delta.

AT currently is an 'outlier' making the above aspect all the more interesting/critical. 

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3 hours ago, stief said:

@jack_sparrow

Did you see LeCam's coffee stop/ Renault/ Ferrari article? Reminded me of your shopping trip routes.

https://www.vendeeglobe.org/en/news/20420/jean-le-cam-cafe-stop

The cartoonists are having fun with it too https://twitter.com/JeanLecam/status/1329515930817323008?s=20

Jean Le Cam is comparing the foilers to Ferraris, and his old generation straight boards boat to a Renault 4L...

image.png.d6205992450965b0712678c129edfa40.png

 

The letter L in French is pronounced the same way than the world "aile", which means... wing. Therefore the humoristic drawing with 4 "wings" (aka foils)

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6 hours ago, nasil2nd said:

This will get the data from the boats in an "semi-automated" way

https://gist.github.com/nas-/6d50ec98baf8925a9f96605213d4bfd4

Basically, you search the boats on the map, you put the link in the variable config, and it will output all the data for the boat.

Great, I have to try this out! Thanks!

How about storing this config in external json-file, and updating the latlon every cycle, maybe with the latlon prediction based on last position, speeed and course? This should allow to "follow" boat automatically?

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FishingFleetHBCourse4.jpg.0075f860d7fb781b67f314c975a7d331.jpg

Finally he is going to the center of it (!), hopefully he has radio contacted with the fishing fleet, and their fckg huge deployed systems (longlines or driftnets. etc) are not in the surface and will not affect him... otherwise he could be going directly at very hi speed to a huge clusterfuck (as with last Route du Rum's Guadeloupe tour)... :ph34r:

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55 minutes ago, ivansh said:

You guys realize that 100nm is nothing in this race, right? The skippers are sailing their own race, with their own routing and macro-level decisions which play out over weeks, not between tracker updates. It seems a bit pointless to talk about boats gaining or losing 20nm, or that someone behind is going 1 knot faster. It's chess, and the skippers are thinking 10 moves ahead, not about if someone is closer to rhumb than they are.

:) 1 minute read  https://www.alexthomsonracing.com/the-hub/2020/11/19/day-12-take-5-with-alex/

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12 hours ago, jack_sparrow said:

Not luck it is onboard AIS instalation, sea state and satellite passes.. 

Good points!

There it is indeed quite a bit of "luck" also. RF on such weak signals is still magic. For instance atmospheric conditions affect the reception a lot, with such a weak signal. Also satellite moving overhead, every symbol of ais message is subjected to different reception, doppler etc. It is hard, it just seems easy when it looks easy. It is not rocket science, but close.

 

12 hours ago, jack_sparrow said:

Things like more efficient antenna splitter, splitting antenna between AIS and VHF and electromagnetic interference from other devices, particular mast mounted. Antenna cabling type and routing and whip antenna plane is maybe favouring a vertical signal noting satellite RX is vertical not horizontal to earth surface.

Actually satellite is not directly overhead usually, so it is not actually vertical transmission, but mostly horizontal beam from antenna. This is lucky, as antenna type used has a null overhead, would not work that well if at all.

You have good points on equipment, but the most important by far is missing, that is the rf ground. Usually these are end fed random length antennas, and they need a solid counterpoise to radiate against. Usually this is more or less not there. Solution would be to use:

1. good traditional rf ground. Hull of the boat, lot of rf screen etc. This is hard in theory to get right, even harder in practise. This is somewhat black art, easy to get somewhat okish, but hard to get good. This is how most boats are done, and I would say 99% of them pretty poorly. VHF will work short distance just fine, but tx as well as reception is lousy on long distance (and also radio heats up a lot).

ant14.jpg

2. use resonant half wave dipole antenna raised high above ground, ie. masthead. No ground needed at all. "Easy" solution, very efficient. This is what I have for VHF and AIS on my boat. reception is stellar, antenna is cheap. Don't know why it is not used more.

1137502581-1244020917-pic-2.jpeg

3. Best solution in my opinion is to use raised, resonant radials, minimum two of those if you want to keep omnidirectional pattern. This is actually best "universal" solution onboard a boat, works very well on seawater, not so well on fresh. This needs very careful setup and a set of exact length radials for every band used. I use this on my boat for HF ham -radio and marine SSB., it works super well, can receive email thousands of miles away from another station. This is an example of such antenna on 15 meter band:

Screen-Shot-2020-11-20-at-8-30-15.png

4. There are other ways, better in theory but hard in practise, like lifted, folded dipole etc.

Disclaimer: I do work on the rf-field for my day job and also do ham radio as a hobby.

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1 hour ago, Kenny Dumas said:

These boats sail faster than the wind. A favorable current reduces the speed of the air over the water. You lose more boat speed through the water than you gain from the favorable current.

What???

A favourable current reduces your drag, increasing your boatspeed, its not like they go backwards. And that makes you go faster, more AWS, win-win?

And even if you disregard drag, favourable current will push you forwards and add to the wind coming from front sector. These boats go so fast that apparent is mostly forward, right?

Quote

The AC boats in San Francisco hunted adverse current downwind. 

Really? Must be some other reason.

Apparent from ahead always on these boats.

You have some source explaining this?

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45 minutes ago, Rafael said:

Finally he is going to the center of it (!), hopefully he has radio contacted with the fishing fleet, and their fckg huge deployed systems (longlines or driftnets. etc) are not in the surface and will not affect him... otherwise he could be going directly at very hi speed to a huge clusterfuck (as with last Route du Rum's Guadeloupe tour)... :ph34r:

 

Are you sure these are fishing boats - they are not classified as such? I would bet they are oil rigs...

Must be a sight, in any case :)

edit. maybe these are some sort of fishing devices or buoys. There are fishing vessels around.

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13 minutes ago, noaano said:

 

Are you sure these are fishing boats? I would bet they are oil rigs... Must be a sight, in any case :)

Nope, not sure at all, just speculating... better if they are (oil rigs)... driftnets or longlines with beacons could be a real nightmare as the debris floating around the area, and with this extrordinary sailor you can be sure to allways expect the unexpected... :)

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Just now, Rafael said:

with this extrordinary sailor you can be sure to allways expect the unexpected...

I bet this extraordinary sailor has a bottle hidden somewhere in case he loses the lead _again_ due to hitting and getting stuck to a fishing net :)

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1 hour ago, Laurent said:

Jean Le Cam is comparing the foilers to Ferraris, and his old generation straight boards boat to a Renault 4L...

image.png.d6205992450965b0712678c129edfa40.png

 

The letter L in French is pronounced the same way than the world "aile", which means... wing. Therefore the humoristic drawing with 4 "wings" (aka foils)

Complete with Renault 4 gear box. :ph34r:

image.jpeg.a61473d5a820620db30c71d89ff603db.jpeg

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UTC 0730

HB 21.9 kts 180 deg, age mins: 6 err: 2.2 corrected latlon: -12.93882 -33.00727

LO 19.8 kts 157 deg, age mins: 2 err: 0.7 corrected latlon: -12.1017 -30.9946

AV 20.5 kts 172 deg, age mins: 19 err: 6.5 corrected latlon: -11.68022 -31.90476

Btw. err-field is predicted error in nautical miles from last ais-update, speed times age of update. Just to give indication on accuracy of reporting.

Worth noting, LO is turning left quite a lot. Wind shift or more permanent change of course?

 

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22 minutes ago, noaano said:

I bet this extraordinary sailor has a bottle hidden somewhere in case he loses the lead _again_ due to hitting and getting stuck to a fishing net :)

HA!... that's Roi Jean's theraphy... glub glub ClacClac fuckfuck... That hidden bottle in HugoBoss is exclusively reserved to spray it in les Sables entry... :D

PD. Thank you for your awesome on the fly data inputs, this is why I love this forum (!)

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1 hour ago, Laurent said:

Jean Le Cam is comparing the foilers to Ferraris, and his old generation straight boards boat to a Renault 4L...

image.png.d6205992450965b0712678c129edfa40.png

 

The letter L in French is pronounced the same way than the world "aile", which means... wing. Therefore the humoristic drawing with 4 "wings" (aka foils)

In addition, Renaults of that period came in various base spec levels: L, TL, TS, TX (I don't think the 4 had a TX spec, was reserved for bigger cars) the L was typically the cheapest, most basic version.... adds to the irony :-)

Cheers, 

                 W.

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6 minutes ago, noaano said:

Actually satellite is not directly overhead usually, so it is not actually vertical transmission, but mostly horizontal beam from antenna. 

Not what occurs in practise. It is actually more vertical than horizontal being recieved by satellite with paths in the same postcode. Low power AIS TX quite OK at satellite altitudes BUT not extra horizontal distance over (but not under) the horizon. That TX beam below that of sat altitude and next to impossible for a narrow TX beam at max gain to find an satellite RX antenna. That said ocean surface can reflect VHF TX upwards, but at a power cost. 

This is of all the issues I listed the one combined with sat pass times that impacts the most on different AIS sat transmission intervals between these boats. 

11 minutes ago, noaano said:

This is lucky, as antenna type used has a null overhead, would not work that well if at all.

Not null but but a bubble depending on gain.

Tip the mast and horizontal suddenly is up in the air and working dandy.  

IMG_20201120_173128.jpg.d2bc6af293b63295d7cef6a11ffd2a71.jpgIMG_20201120_173243.jpg.3aab5e6b3b48ef915a6ae89394e4b3be.jpg

22 minutes ago, noaano said:

You have good points on equipment, but the most important by far is missing, that is the rf ground. Usually these are end fed random length antennas, and they need a solid counterpoise to radiate against. Usually this is more or less not there. Solution would be to use:

1. good traditional rf ground.

AIS uses VHF and marine VHF have independent ground planes built into antenna requiring no ground or counterpoise. Hence why I didn't bother with it. 

You mention it 

47 minutes ago, noaano said:

2. use resonant half wave dipole antenna raised high above ground, ie. masthead. No ground needed at all. "Easy" solution, very efficient. This is what I have for VHF and AIS on my boat. reception is stellar, antenna is cheap. Don't know why it is not used more.

Marine SSB MF/HF on other hand DOES require either ocean ground surface OR a onboard 'counterpoise' system.

It is this which you have described.

An exception is the 2nd RX antenna for a DSC Marine MF/HF that doesn't employ it.

36 minutes ago, noaano said:

Disclaimer: I do work on the rf-field for my day job and also do ham radio as a hobby.

You know far more than me. Mine only years practical experience. Biggest problem I have observed is people not knowing the difference between radio and electrical grounds and end up making a galvanic corrosion clusterfuck and radios that don't work. 

Note I have tested both traditional below waterline ground and a in vessel counterpoise system in real life on a DSC HF. Jury is still out though with proper testing gear I suspect the latter will come out on top for performance and gets rid of a below waterline constraint. 

Sorry about thread drift. 

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Official tracker update is just coming out, but just wanted to note that Alex also turned left/east a bit just after clearing that mystery field, following Thomas' example.

HB 23.2 kts 166 deg, age mins: 2 err: 0.8 corrected latlon: -13.05226 -32.98758
LO 19.9 kts 157 deg, age mins: 2 err: 0.7 corrected latlon: -12.19453 -30.95934

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59 minutes ago, noaano said:

Good points!

There it is indeed quite a bit of "luck" also. RF on such weak signals is still magic. For instance atmospheric conditions affect the reception a lot, with such a weak signal. Also satellite moving overhead, every symbol of ais message is subjected to different reception, doppler etc. It is hard, it just seems easy when it looks easy. It is not rocket science, but close.

 

Actually satellite is not directly overhead usually, so it is not actually vertical transmission, but mostly horizontal beam from antenna. This is lucky, as antenna type used has a null overhead, would not work that well if at all.

You have good points on equipment, but the most important by far is missing, that is the rf ground. Usually these are end fed random length antennas, and they need a solid counterpoise to radiate against. Usually this is more or less not there. Solution would be to use:

1. good traditional rf ground. Hull of the boat, lot of rf screen etc. This is hard in theory to get right, even harder in practise. This is somewhat black art, easy to get somewhat okish, but hard to get good. This is how most boats are done, and I would say 99% of them pretty poorly. VHF will work short distance just fine, but tx as well as reception is lousy on long distance (and also radio heats up a lot).

 

2. use resonant half wave dipole antenna raised high above ground, ie. masthead. No ground needed at all. "Easy" solution, very efficient. This is what I have for VHF and AIS on my boat. reception is stellar, antenna is cheap. Don't know why it is not used more.

 

3. Best solution in my opinion is to use raised, resonant radials, minimum two of those if you want to keep omnidirectional pattern. This is actually best "universal" solution onboard a boat, works very well on seawater, not so well on fresh. This needs very careful setup and a set of exact length radials for every band used. I use this on my boat for HF ham -radio and marine SSB., it works super well, can receive email thousands of miles away from another station. This is an example of such antenna on 15 meter band:

 

4. There are other ways, better in theory but hard in practise, like lifted, folded dipole etc.

Disclaimer: I do work on the rf-field for my day job and also do ham radio as a hobby.

No offence but what you have posted here is mostly irrelevant to the AIS situation under discussion... You are banging on about HF techniques when AIS is VHF. The sea is a feking good ground plane so no need for your radials (they are pointless) the VSWR on VHF antennas is generally very good.. Don't worry readers your radio is not going to "heat up" unless you have a major fault. AS soon as I see GTO-xx or whatever on a diagram I know that it was draw by somebody who has read a couple of bad books....  

You are partially correct when you mention that the "type of antennas" that are used radiate horizontally the radiation pattern is something like a flat bottomed donut as this is the case with a typical yacht masthead whip. But, and I'm not sure, they are probably using antennas that are radiating more in the vertical plane to deliberatly improve satellite reception. 

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2 minutes ago, littlechay said:

You are partially correct when you mention that the "type of antennas" that are used radiate horizontally the radiation pattern is something like a flat bottomed donut as this is the case with a typical yacht masthead whip. But, and I'm not sure, they are probably using antennas that are radiating more in the vertical plane to deliberatly improve satellite reception.

Actually chay, if there were a way I would rather find an antenna to reduce satellite reception. I would rather my AIS signal was just for its intended purpose and if I want anyone outside my immediate vicinity to know where I am I can use other means.

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3 minutes ago, jack_sparrow said:

Not what occurs in practise. It is actually more vertical than horizontal being recieved by satellite with paths in the same postcode. Low power AIS TX quite OK at satellite altitudes BUT not extra horizontal distance over (but not under) the horizon. That TX beam below that of sat altitude and next to impossible for a narrow TX beam at max gain to find an satellite RX antenna. That said ocean surface can reflect VHF TX upwards, but at a power cost. 

 

This contradicts on the reception I see in the real life. I have just infact compared reception times reported from Marinetraffic and TLE-derived positions from satellite, trying to work out which one is the satellite they are using. At the instant of reception, the satellites are way of horizontally most of the time. All the TLEs are available, you can see for yourself:

https://www.celestrak.com/NORAD/elements/

 

3 minutes ago, jack_sparrow said:

Not null but but a bubble depending on gain.

 

If you have a single dipole element, or half dipole, this is a text book definition of null - this is pure field theory. All that you receive on antenna axis is multipath reflections, nothing from the antenna directly.

 

3 minutes ago, jack_sparrow said:

AIS uses VHF and marine VHF have independent ground planes built into antenna requiring no ground or counterpoise. Hence why I didn't bother with it. 

 

They do have all sort of loading coils and stuff. They are usually pretty poor performing. You can see this for yourself by buying a few tens of usd antenna analyser from Aliexpress, antenna WSRV is all over the place which is a way to say rf efficiency is piss poor.

That is (partly) why onboard commercial and military ships youll either see VHF dipole antennas or half dipoles with angled radials. Same for _every_ VHF ground based base station or coastal radio or SAR site etc:

Antenne_gp_vhf_3.jpg

 

I do not understand why marine (VHF) radio involves so many myths like "antenna requiring no ground or counterpoise". It simply is not true, it is physics. You can get some signal for sure, but you would get so much better signal with much more range when you need it in bad weather and/or distress with minimal extra effort and spending less than a case of beer costs in many places. Simply strange.

 

3 minutes ago, jack_sparrow said:

Marine SSB MF/HF on other hand DOES require either ocean ground surface OR a onboard 'counterpoise' system.

 

It is the same for every frequency, physics is the same. VHF jus forgives you a lot, as distances are short and signal is so strong. Better to do it better, always.

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16 minutes ago, littlechay said:

No offence but what you have posted here is mostly irrelevant to the AIS situation under discussion... You are banging on about HF techniques when AIS is VHF. The sea is a feking good ground plane so no need for your radials (they are pointless) the VSWR on VHF antennas is generally very good..

Sea is very good ground plane, if antenna is coupled to sea. If not, it does not help that much.

Anyways, this is another discussion, but using a dipole ais antenna is way cheap way to increase your ais range. 

Lets continue following the race.

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2 minutes ago, noaano said:

 

I do not understand why marine (VHF) radio involves so many myths like "antenna requiring no ground or counterpoise". It simply is not true, it is physics. You can get some signal for sure, but you would get so much better signal with much more range when you need it in bad weather and/or distress with minimal extra effort and spending less than a case of beer costs in many places. Simply strange.

 

I certainly never said that no counterpoise is required. What is not needed is a counterpoise made from bits of metal. You have a great groundplane called the ocean :)

Since the advent of satellite AIS antennas have been available to transmit to the receivers aboard the satellites....  that's kind of the point other then monitoring the signals meant for earth bound use. 

Here is some reading on why and what ;) https://www.researchgate.net/publication/335825822_The_Impact_of_Space-Based_AIS_Antenna_Orientation_on_In-Orbit_AIS_Detection_Performance/link/5d83ea7ca6fdcc8fd6fafd80/download

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1 minute ago, littlechay said:

I certainly never said that no counterpoise is required. What is not needed is a counterpoise made from bits of metal. You have a great groundplane called the ocean :)

Yes, but the signal needs to be coupled to sea somehow, antenna is a circuit that needs to go around. Angled radial on base of the antenna or full dipole not requiring counterpoise is always superior to "faking" the ground by using loading coils. 

As I said, VHF is forgiving. You can get signal out with no antenna attached. It still does not mean you shouldn't try to make it good.

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1 minute ago, noaano said:

Sea is very good ground plane, if antenna is coupled to sea. If not, it does not help that much.

Anyways, this is another discussion, but using a dipole ais antenna is way cheap way to increase your ais range. 

Lets continue following the race.

Well if you use a halo or similar dipole it may be some use.. But a conventional simple dipole is not much use becase it has to be isolated, supported from the end and isolated from any metal... bit of a bugger to achieve in light, strong, low wind resistance form, at height on a yacht. 

A perfect dipole antenna will give you a gain of 3dBi .... Vertical antennas in many configurations give superior gain. 

There are more ways of coupling to the sea than with metal .... The antenna is coupled to the sea... don't worry 

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17 minutes ago, spyderpig said:

Actually chay, if there were a way I would rather find an antenna to reduce satellite reception. I would rather my AIS signal was just for its intended purpose and if I want anyone outside my immediate vicinity to know where I am I can use other means.

Attach an attenuator on antenna cable, few dbs should do the trick. Easy to try how much is needed, by looking at MT.

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1 hour ago, noaano said:

Actually satellite is not directly overhead usually, so it is not actually vertical transmission, but mostly horizontal beam from antenna. This is lucky, as antenna type used has a null overhead, would not work that well if at all.

41 minutes ago, jack_sparrow said:

Not null but but a bubble depending on gain.

Tip the mast and horizontal suddenly is up in the air and working dandy.  

 IMG_20201120_173128.jpg.d2bc6af293b63295d7cef6a11ffd2a71.jpgIMG_20201120_173243.jpg.3aab5e6b3b48ef915a6ae89394e4b3be.jpg

 

24 minutes ago, noaano said:

If you have a single dipole element, or half dipole, this is a text book definition of null - this is pure field theory. All that you receive on antenna axis is multipath reflections, nothing from the antenna directly.

 

Boat/mast/antenna heel is NOT textbook or pure field theory.

Horizontal goes more vertical above the horizon. 

It happens.....it's real. :D

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Back to the race... Alex holds his lead like a champ in this sched, vamos Melon... awesome challenge and battle with the two youngBloods!, the three extending big time to the whole peloton... back there Tripon with more problems (sadly looks like the race is near over for him...) 

And Arkea Paprec smoking! just marked the new temp 24hr race record with 507.3Nm, I bet Juan KO is now happy as a pig in the mud with his last bullet... :D crossfingered truly hoping not to see under his belt another Arkea PapWreck...

image-r-1600-900.thumb.jpg.298aaaa43b3fd63df5318b0b5491e508.jpg

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4 minutes ago, jack_sparrow said:

Boat/mast/antenna heel is not textbook.

Horizontal goes more vertical above the horizon. 

It happens.....it's real. :D

This is true and I agree :) I forgot they are sailing :)

Lets continue watching the race!

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UTC 0830.

Alex has shifted a new gear, speed just shot up considerably after clearing that field-of-whatever:

HB 26.5 kts 184 deg, age mins: 5 err: 2.2 corrected latlon: -13.34879 -32.95065

LO 21.7 kts 165 deg, age mins: 2 err: 0.7 corrected latlon: -12.47065 -30.86279


 

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4 hours ago, stief said:

IIRC, a few years ago Leov?, or another anarchist here recommended signing up for their newsletter. Their translation page, linked in the newsletter, makes it easy to follow for a non-native French reader

Could be, I did talk to PYL (Editor) when he started it , and I get an English weekly email for over a year. Saves translating for you ?
https://www.tipandshaft.com/en/
And T&S is his humor style.

And this sponsored article about NKE was nice, NKE is coming back, or at least trying too.
https://www.tipandshaft.com/en/on-the-market/sponsored-article-about-nke-is-repositioning-itself-in-the-high-performance-pilots-market/

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17 minutes ago, tallyho said:

.. if you want a dick measuring competition just send each other photo's and be done with it

No, we first discuss the measuring protocol, and will not agree...

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5 minutes ago, noaano said:

UTC 0830.

Alex has shifted a new gear, speed just shot up considerably after clearing that field-of-whatever:

HB 26.5 kts 184 deg, age mins: 5 err: 2.2 corrected latlon: -13.34879 -32.95065

LO 21.7 kts 165 deg, age mins: 2 err: 0.7 corrected latlon: -12.47065 -30.86279


 

Potential record breaking conditions for him and the 2 boys in the next 24 hours, sea state looks a bit crossed from the East but quite fine until unfamous Cabo Frio's static front wall with contrary and confused crossed seas

CaboFrioWavesSat.jpg.6f6286a7dd0936e5c24560c00127bfcd.jpg... 

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10 minutes ago, staysail said:

3 hours between updates is a long time. Might as well chat about something vaguely relevant?

Now the satellite AIS update rate seems to be like every 3 minutes. I have never seen such a good reception, maybe it is combination of ideal atmospheric conditions and also maybe there is less other traffic. They are also fairly close to the equator, that helps also.

It will be interesting to see how the reception is on southern ocean...

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12 minutes ago, LeoV said:
5 hours ago, stief said:

IIRC, a few years ago Leov?, or another anarchist here recommended signing up for their newsletter. Their translation page, linked in the newsletter, makes it easy to follow for a non-native French reader

Could be, I did talk to PYL (Editor) when he started it , and I get an English weekly email for over a year. Saves translating for you ?

Me too and I'm pretty sure it was you Leo to thank. 

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Every person subscribed helped him the first year :) and I knew a few SA idiots would sign up.

From the PRB site;

STATEMENTS BY KEVIN JOINT EARLY AFTERNOON BY PHONE: 

“I'm not very happy because I lost around 20 miles in the Doldrums. I know the road is long but it annoys me anyway. I try not to ignite even if this regatta in contact is brilliant. I am currently sailing against a very good boat led by Louis Burton. We talk a lot about speed, we compare speeds. Me, I have a boat from 2009, it should not be forgotten. So when I go at the same speed as the leading boats, I'm really happy. I was a little tired yesterday but I slept well the last few hours. I recharged the batteries and that is important. "
https://sport.prb.fr/en-mer/actus/235-jour-11-prb-dans-l-hemisphere-sud

I did read somewhere Burton and Escoiffier are family as Burton's wife is the connecting link.

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35 minutes ago, Rafael said:

Back to the race... Alex holds his lead like a champ in this sched, vamos Melon... awesome challenge and battle with the two youngBloods!, the three extending big time to the whole peloton... back there Tripon with more problems (sadly looks like the race is near over for him...) 

And Arkea Paprec smoking! just marked the new temp 24hr race record with 507.3Nm, I bet Juan KO is now happy as a pig in the mud with his last bullet... :D crossfingered truly hoping not to see under his belt another Arkea PapWreck...

image-r-1600-900.thumb.jpg.298aaaa43b3fd63df5318b0b5491e508.jpg

That's great to see. She looks like a fast boat. He doesn't have as much experience as the top skippers and a bit similar in time on the water to L'Occitane. As we know the boat is one thing but the skippers are more important to performance. Jean Le Cam vindicates that IMO.

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Louis Burton’s performance continues to impress in his seemingly unmodified (looks like original foils) gen 1 foiler. Caught and overtook Boris and Sam in their turbo’d boats and looks like he’ll shortly overtake Kevin on PRB who at one point was in the lead pack. This could all change when the boats turn downwind of course but I thought credit where credits due to him

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10 hours ago, Corryvreckan said:

The interesting thing to me in this video is that all three of those widely diverging options get to the waypoint within about eight hours of each other.  This sort of highlights how un-helpful the DTL measures are, since if the boats really did split that much, the DTL would presumably be huge for the boats in the west, but bear little resemblance to how soon they will get there.

That is why a TTG/ETA to a virtual waypoint is more relevant than the DTL's. I think that the VG does not have the boat specific polars for the fleet to calculate the TTG across the fleet. DTF is the next best thing. And cheaper to run daily. If @Volodia adds routing projections to his tracker, based on polars @Hitchhiker  and me can provide, we are in business. I started working on a very rough IMOCA 60 class assessment for boat polars in the VG.

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48 minutes ago, noaano said:

Now the satellite AIS update rate seems to be like every 3 minutes....

I have run an algorithm using that 3 minutes update rate that says HB has 13.8 degrees of heel and Alex just took a piss that brought the ocean ground plane into play for his AIS antenna. :lol:

IMG_20201120_185536.jpg

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5 minutes ago, jack_sparrow said:

I have run an algorithm using that 3 minutes that says HB has 13.8 degrees of heel and Alex just took a piss that brought the ocean ground plane into play for his AIS antenna. :lol:

IMG_20201120_185536.jpg

simple physics, the angle of his dipole created a mulit-path counterpoise frequency that interfered with his 3dBi halo attenuator... or something

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Question for the routing hacks:

Is AT aiming for the northern side of the Low presently at roughly 29° 30’’ S and 33° 25’ W predicted to move E?

He seems pretty confident in his choice since there’s no attempt to cover (even though he’s not immune to doubt: “I try not to constantly think about who is behind me, chasing me. I used to be a bit like that but not so much any more.”)

Could be a decisive point today, if this turns out to be a major split of the front runners.

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13 hours ago, TheDragon said:

Boris just had another "episode". I wonder if we had this data from each boat we would see the same kind of thing?Screen Shot 2020-11-19 at 2.50.48 PM.png

So he's on port tack with a TWA  beam/broadish reach implying an AWA close reach.

The leeward shroud loads up and the windward shroud unloads till they are both the same tension.

Contemporaneously the forestay unloads while the bobstay (outer forestay) loads up slightly.

About the only 'scenario' I can think of is a nice, fast, slightly-past head-to-wind round up.

Sounds like a lot of fun at 20+ knots on a turboed 60 footer by yourself.

Edited by t.rex
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18 minutes ago, t.rex said:

So he's on port tack with a TWA  beam/broadish reach implying an AWA close reach.

The leeward shroud loads up and the windward shroud unloads till they are both the same tension.

Contemporaneously the forestay unloads while the bobstay (outer forestay) loads up slightly.

About the only 'scenario' I can think of is a nice, fast, slightly-past head-to-wind round up.

Sounds more like dunking the leeward outrigger / deck spreader due to excessive heel?

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There is not really a dunking. The heel angle of the boat goes down from ~10° before to ~3° during the episode and back then up to ~12°. (10 minute avg before and after)
Rig loads on both outrigger are about equal during the episode. 9.4t on port and 9t stbd. Makes sense, port has more load before and after.

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3 minutes ago, Chasm said:

There is not really a dunking. The heel angle of the boat goes down from ~10° before to ~3° during the episode and back then up to ~12°. (10 minute avg before and after)
Rig loads on both outrigger are about equal during the episode. 9.4t on port and 9t stbd. Makes sense, port has more load before and after.

fair enough

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46 minutes ago, t.rex said:

So he's on port tack with a TWA  beam/broadish reach implying an AWA close reach.

The leeward shroud loads up and the windward shroud unloads till they are both the same tension.

Contemporaneously the forestay unloads while the bobstay (outer forestay) loads up slightly.

About the only 'scenario' I can think of is a nice, fast, slightly-past head-to-wind round up.

Sounds like a lot of fun at 20+ knots.

 

A sudden lull (as in puffy conditions) would do it.  The loads on the two shrouds seem to equalize as pressure comes off the sails.  I can recall cases where it happened when I got blanked by another boat in a harbour race, though it's hard to picture that happening on the open ocean.  Are the doldrum winds flukey enough for something like that?

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Alex has pulled a few miles on the Verdier Twins behind him and according to a quick measurement has around 740nm in these conditions until he has to pull the trigger to start turning East. As the wind is more aft we'll see if the Boss is indeed the Boss? At the moment his Westerly position has given him a little more pressure than Linked Out etc. The decision as to when to turn East looks tight ATM but a clearer window may appear as he gets closer. I noticed his heart rate was up there so I dare say he has been working the boat. Good on him so far. Keeping 2 hungry wolves at bay for days is no mean feat......! :ph34r:

 

Wolf-1-1090x380.jpg

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