Sydney To Hobart 2018

Potter

Super Anarchist
2,116
355
As I understand it they are designed not to activate via a wave on deck. There is some sort of flotation trigger. False alarms may occur now and then but someone keeps telling me isn't it better to be safe than sorry? 
The danger is crying wolf. The more false starts the slower the response to a real alert. Auto switches are not reliable enough yet. 

 

SCANAS

Super Anarchist
6,788
494
Brisbane
Yep & if you did get a false set off (because it’s windy & you’ve got waves coming over the deck) are you going to know before the chopper comes overhead, assuming it’s all on & you aren’t monitoring the comps also are you really going to repack the auto device in the middle of all that. 

 

Snowden

Super Anarchist
1,164
631
UK
As I understand it they are designed not to activate via a wave on deck. There is some sort of flotation trigger. False alarms may occur now and then but someone keeps telling me isn't it better to be safe than sorry? 
Designed not to, but in practice they do. Loads of them going off in this year's Round Ireland with no associated MOB.

 

JonRowe

Super Anarchist
1,885
1,013
Offshore.
There are enough manual false alarms for PLBs (being switched on in pockets etc) that they make a point of reminding everyone they will be called on the sat phone when they do go off... Definitely more design work needed to go auto...

 

jack_sparrow

Super Anarchist
37,393
5,094
The auto switching of 406 PLB's (along  with some other issues) has been tied up with the US Federal Communications Commission/Radio Technical Commission for Maritime Services (RTCM) Stsndards and SOLAS for specs for the last 2/3 years.

However this is not in the form of a standalone unit but a Combined 406/AIS PLB device. It will probably be in this combined form factor that auto switching the 406 signal will first appear, if at all.

Note.

The first combined device to come out will be probably this crowds 4 frequency device and then only for commercial vessels first, not the recreation market and only then when the form size is PLB friendly. While it says released here in this 2 year old article, it is bogged down in approval stuff.

https://www.maritimejournal.com/news101/industry-news/first-four-frequency-epirbs-launched

mcmurdo_smartfind_g8_ais_epirb_collage_cpanbojpg.jpg

 
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JonRowe

Super Anarchist
1,885
1,013
Offshore.
I like having two personally, feels more reassuring having "alternatives", although the Volvo crews had two AIS and a PLB from memory, so maybe an AIS beacon and a combined would make more sense for them?

The main problem with HF in the S2H has the ridiculous check requirements, you have to get it working with one dodgy marine rescue transceiver thats not going to be the main source of help in a crisis? They did allow boats that had successfully performed scheds in other races to bypass that at one point, does anyone know if they're doing so this year? (e.g bypass the marine rescue radio check requirement if you were 5/5 in the BWPS scheds?) Ongoing practical checks like that make more sense to me...

 

Livia

Super Anarchist
4,038
1,103
Southern Ocean
Anyone that complains about HF is just an ignorant dick that does not understand how HF works and can’t be fucked learning about it.

That includes race committees.

Like the Keppel Race a few years ago that had a midday sked on 2 MHz to Charleville. THat was just ignorance.

So having used HF for almost 40 years now here are a few tips on the installation which is usually the first problem to deal with.

Put the auto tuner as close to the antenna base a possible, like right under it.

Ignition cable is best for this lead due to better insulation.

Hard wire the set straight to the batteries Over the shortest distance.

Disconnect and clean the ground plane at least twice a year.

Most HF problems are connection problems.

Have batteries at max before transmission so charge just before or durring the sked

Take time to learn about propagation so you understand why you use which frequency.

There are so  few things that HF users will argue about but one is never have a continuous plane perpendicular or the antenna so always put a rope lashing in the lifelines.

But as there say HF is sometimes more art than science

Also understand your set for instance which is why you often miss the first part of a transmission, that is operator error.

Lastly, older sets such some Codans were built to an AUS standard ( for military use) and can nave twice the output of a flash new ICOM built to the international standard.

 
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Third Reef

Member
129
33
Bass Strait
So having used HF for almost 40 years now here are a few tips on the installation which is usually the first problem to deal with.

There are so  few things that HF users will argue about but one is never have a continuous plane perpendicular or the antenna so always put a rope lashing in the lifelines.
Thanks Good advice.

Could you expland on this last point ? I don’t quite understand. How do you lash the life lines ?

3R

 

Livia

Super Anarchist
4,038
1,103
Southern Ocean
 It has also struck me that there are needless DSQs in the Hobart with the Green Cape rule.

Although it has not happened to me, I have wondered about this.

You have to use ch 608 from memory (which is duplex but that should not matter with this)

But if you were trying to call on ch 608 in the middle of the day to the Radio vessel if you where say 80 to 120 miles away you would be too far for line of sight but most importantly too close to land a 6 MHz transmission. (whereas over 250 miles would be fine)

That is why boats have complained that they could call Sydney and other coast stations for instance but not the Radio vessel but got a dsq.

So there is nothing wrong with the set just the wrong frequency is prescribed for that distance for that time of day.

Transmission on 2mhz would most likely work , say use 2524 for instance.

My 20 cents!

 
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Livia

Super Anarchist
4,038
1,103
Southern Ocean
Thanks Good advice.

Could you expland on this last point ? I don’t quite understand. How do you lash the life lines ?

3R
TR, use VB cord lashing so you does not have an unbroken conductive plane (ie lifeline secured with turnbuckles for instance) at right angles to the antenna.

That said a friend uses his forestay and backstay as his antenna together with the perpendicular plane. But his boat is steel.

So more art than science.

Be interesting to use a whole carbon TP2 with carbon rigging as an antenna to see how it works.

 

duncan (the other one)

Super Anarchist
5,508
525
Siderney
Be interesting to use a whole carbon TP2 with carbon rigging as an antenna to see how it works.
badly, I suspect.

The probability of having an unbroken conductor end to end in the hull is pretty low. Lots of little semi-insulated segments instead.

You'd risk creating a hotspot somewhere and damaging the laminate.

For the rigging, carbon is a very lossy conductor;  the impact of damaging it with RF power is somewhat more catastrophic.

 

jack_sparrow

Super Anarchist
37,393
5,094
Lastly, older sets such some Codans were built to an AUS standard ( for military use) and can nave twice the output of a flash new ICOM built to the international standard.
Actually not right and things haven't changed.

There is no such thing as an international marine standard. One of the reasons why HF is so expensive is there are currently 2/3 country commication authority standards in play so of the one model, 2/3 versions have to be produced, Australia has the best and is why Aust pay around $1k more than their US counterpart for the same model.

 
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jack_sparrow

Super Anarchist
37,393
5,094
It has also struck me that there are needless DSQs in the Hobart with the Green Cape rule......That is why boats have complained that they could call Sydney and other coast stations for instance but not the Radio vessel but got a dsq...
The RC could reduce that probability today by allowing those with a GMDSS/DSC HF set on board to simply send their "passing Green Cape" as a digital page, not as a voice message.

It is boat (MMSI) to boat (MMSI)/Land Station specific communication, guaranteed to get through, will be automatically resent for up to 5 minutes until a digital acknowledgement is recieved via a dedicated DSC watchkeeping receiver (which automaticaly scans all MF/HF DSC channels in rapid sequence). An audible alarm is activated when DSC messages are received.

This transmission to recieve process should take less than 10 seconds.

Voice communication with the RC could then be initiated if desired by responding on the voice working channel indicated with that digital acknowledgement or page. 

The days of trying different channels at message initiation, a HF squarking noisely away on standby and wondering if your message has got through are long gone. This HF paging procedure is virtually identical to than used between GMDSS/Inmarsat C terminals.

 
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Chucky

Anarchist
535
42
Melbourne
Anyone that complains about HF is just an ignorant dick that does not understand how HF works and can’t be fucked learning about it.

That includes race committees.

Like the Keppel Race a few years ago that had a midday sked on 2 MHz to Charleville. THat was just ignorance.

So having used HF for almost 40 years now here are a few tips on the installation which is usually the first problem to deal with.

Put the auto tuner as close to the antenna base a possible, like right under it.

Ignition cable is best for this lead due to better insulation.

Hard wire the set straight to the batteries Over the shortest distance.

Disconnect and clean the ground plane at least twice a year.

Most HF problems are connection problems.

Have batteries at max before transmission so charge just before or durring the sked

Take time to learn about propagation so you understand why you use which frequency.

There are so  few things that HF users will argue about but one is never have a continuous plane perpendicular or the antenna so always put a rope lashing in the lifelines.

But as there say HF is sometimes more art than science

Also understand your set for instance which is why you often miss the first part of a transmission, that is operator error.

Lastly, older sets such some Codans were built to an AUS standard ( for military use) and can nave twice the output of a flash new ICOM built to the international standard.
I agree about the Codan HF radios, the HF unit I have on my boat is always one of the best transmitted signals when we are racing in fleets of around 12 boats compared to the others with Icom radios. I find the HF radios excellent when set up correctly as Lydia has stated above. I could not believe how well my radio reception was in Osaka bay talking to Charleeville radio! 

 

jack_sparrow

Super Anarchist
37,393
5,094
Lastly, older sets such some Codans were built to an AUS standard ( for military use) and can nave twice the output of a flash new ICOM built to the international standard.


I agree about the Codan HF radios, the HF unit I have on my boat is always one of the best transmitted signals when we are racing in fleets of around 12 boats compared to the others with Icom radios. 
I suspect a old Codan 9390 rated at 125w PEP output. Codan have now departed the marine recreational class HF party. The Icom equivalent then and today is the same 125w PEP output.

There is no international standard. Maximum transmitting power and others are features not plucked out of the air by manufacturers, but is specified by the communication authority for each country having regard to its standards and those set by the International Telecommunication Union (ITU) and then pulled together and nominated by that country for the particular classes of Ship Station Licences. Manufactures then build to match a country's standard.

So actually what you have is not a more powerful transciever by brand comparison but a better installed and maintained system incl energy source compared to others.

 
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Recidivist

Super Anarchist
... never have a continuous plane perpendicular or the antenna so always put a rope lashing in the lifelines.
I had never heard of this!!!!

And apart from using HFs for a decade longer than you Lydia, I also was a Radio Tech with DCA for 13 years, and worked on many HF installations (including building the new HF Transmitter Station in Darwin after Tracy).  I can see the issue, but fark, the things you learn here!!  I DID know enough to never take a leak over the side while holding the capshroud if it was sched time ...

The corollary of this is using the lifelines AS the antenna, as Thunderbolt did in '69 or '70 when dismasted in the Hobart.  They were closer to NZ than OZ when they were finally forced to Mayday, but the signal got through - horizontally polarised rather than vertically, but it worked when they didn't have many options left!

 

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