AIS connected to "hot battery bus" - why?

[wonkywinch]

I was thinking more about the clutter on the CP screen.

That's easy done in your chart plotter layers settings. Better visibility of you by others always helps, ask any cyclist!

My own problem solved. It was finger trouble. Main bus is depowered by master switch next to batteries but leaves mains sockets live when connected to shore power (for heater & dehumidifier).

 

[Buck Turgidson]

I’d like to thank this thread for prompting me to look at marine traffic. Now i challenge all to explain why my boat was sending ais position just once a day at around 12:45z.

 

[Refueler]

I’d like to thank this thread for prompting me to look at marine traffic. Now i challenge all to explain why my boat was sending ais position just once a day at around 12:45z.

Marine Traffic is not real time unless you pay for full licenced version (full access and data is not cheap !!) ..... most info is historical ... plus you are tx'g on B class (B or B+ little difference) which means you are slotting in with other tx's where A class has slots etc.
Even the registered version we use in my Co has limitations as to when data is valid for ...

Its also worth seeing the date of the 1245 tx ... because MT and other sites have habit of having old data displayed ... sometimes it can stay on display for a couple of days or more. My C38 even though fully off - displayed same pos'n for 3 days !!

 

[Buck Turgidson]

Marine Traffic is not real time unless you pay for full licenced version (full access and data is not cheap !!) ..... most info is historical ... plus you are tx'g on B class (B or B+ little difference) which means you are slotting in with other tx's where A class has slots etc.
Even the registered version we use in my Co has limitations as to when data is valid for ...

Its also worth seeing the date of the 1245 tx ... because MT and other sites have habit of having old data displayed ... sometimes it can stay on display for a couple of days or more. My C38 even though fully off - displayed same pos'n for 3 days !!

Wrong. approx same time each day then two days nothing then same time for a couple of days.
It’s fixed now but there is a reason for the behavior which has nothing to do with marine traffic website.

 

[dunedin]

That's easy done in your chart plotter layers settings. Better visibility of you by others always helps, ask any cyclist!

My own problem solved. It was finger trouble. Main bus is depowered by master switch next to batteries but leaves mains sockets live when connected to shore power (for heater & dehumidifier).

I am confused by your post. Surely the domestic 12V system is NEVER on the same switch as the 230V shore power?
(And AIS never on the 230V system on a yacht)

 

[Refueler]

Wrong. approx same time each day then two days nothing then same time for a couple of days.
It’s fixed now but there is a reason for the behavior which has nothing to do with marine traffic website.

I was offering info about MT site .. which was a possible answer - but because you now update with more info - I can agree that MT's lack of real time is not the reason for your situation.

No need for the sarcasm or derision. It is the season of Goodwill to all you know ...

 

[Buck Turgidson]

I was offering info about MT site .. which was a possible answer - but because you now update with more info - I can agree that MT's lack of real time is not the reason for your situation.

No need for the sarcasm or derision. It is the season of Goodwill to all you know ...

No sarcasm intended. You will feel very superior when you learn the answer.

 

[ShinyShoe]

One skipper leaves his AIS on all the time.
Monitors it from home.
If the boat starts to move..!

Yip. Accident or theft. If the thief won't find it easy to switch off they may not know it's tracking them.. rare a boat is nicked though.

Nowadays there seem to be loads of boats leaving their AIS transmitting all winter when stored ashore in a cradle, and unable to move unless lifted by a large yard hoist.

If it's hard wired?
Or you want to know the yard are moving it?
Plenty not so practical so if builders fit this way...bit stays that way

It's a B&G NAIS500 which has a silent mode option switched via a pair of wires (no option on chart plotter). I did fit a switch for "stealth mode" but it's behind the hinge instrument panel. I'd rather depower the whole electronics kit so I don't hurry it towards the right hand side of the bathtub curve.

You could (I dunno why you'd want steal mode) use a relay to take the nav power being off as a switch on the stealth

Satellite requisition time.

It can take 20 mins to get a fix and I am usually well off the mooring in that time. As I pass through a busy military port, Plymouth, there is a lot of shipping and I like to be 'electronically' waving at everybody. Longroom (VTS) can also see me.

If it's taking 20mins are you electronically waving from the right place?

You are making an assumption there, that I am using external GPS antennas. Actually, I am not a fan of them as they get in the way and fail from time to time. From cold both the AIS and VHF take time to build their tables of where the satellites are to get a good fix.

You need to use your boat more! They should have the table stored in memory and only be very cold starting if not used for several months. Even then, PLB cold start and get a fix in <3min normally

Wrong. approx same time each day then two days nothing then same time for a couple of days.
It’s fixed now but there is a reason for the behavior which has nothing to do with marine traffic website.

Solar peak was my guess.

 

[wonkywinch]

I am confused by your post. Surely the domestic 12V system is NEVER on the same switch as the 230V shore power?
(And AIS never on the 230V system on a yacht)

I know that but since Beneteau integrate the 240 and 12v into one switch panel, I wasn't sure initially whether there might be a contactor in the shore power feed that would be switched off by disconnecting the master 12v supply. There isn't as I discovered in my journey of learning boat electrics.

 

[Sandy]

You need to use your boat more! They should have the table stored in memory and only be very cold starting if not used for several months. Even then, PLB cold start and get a fix in <3min normally

I'm retired, I am using the boat almost daily between March and November. Hence the 'pain' of the AIS and VHF rebuilding their tables. Neither have non-violate memory.

 

[ShinyShoe]

I need to add your models to my "what not to buy"...

... GPS should be holding the tables and doing hot, warm and cold fixes. Only a cold fix should take more than a few seconds. It

Last time I worked with a GPS that seemed to want to cold start EVERY time was about 2000.

It feels like incredibly poor design and potentially a 20y lifespan on a product.

 

[Refueler]

I need to add your models to my "what not to buy"...

... GPS should be holding the tables and doing hot, warm and cold fixes. Only a cold fix should take more than a few seconds. It

Last time I worked with a GPS that seemed to want to cold start EVERY time was about 2000.

It feels like incredibly poor design and potentially a 20y lifespan on a product.

The normal GPS for marine use ... handheld r fixed - have literally always had memory of the tables ... the only time extended time to fix is if you moved more than a reasonable distance from last known switch off.

Even my old Magellan HH unit from way back - still works today fine ... the only hiccup was when it had the timing jump ... that all older sets had to get through ... I agree it can take some few minutes to get going - but that's because it gets moved around and left off a lot !! My old standard eTrex boots up quick from cold ...

Strange to have any not doing at least that ...

 

[Sandy]

I need to add your models to my "what not to buy"...

... GPS should be holding the tables and doing hot, warm and cold fixes. Only a cold fix should take more than a few seconds. It

Last time I worked with a GPS that seemed to want to cold start EVERY time was about 2000.

It feels like incredibly poor design and potentially a 20y lifespan on a product.

Just check that anything that you buy has a non-violate memory and an internal battery.

Given the design life and development time all 'modern kit' must be well over over 10 years old.

Both the AIS and VHF have been on the boat for over 10 years, but I really don't want to replace them as they will outlast me. It would be a complete waste of beer tokens and environmentally unsound when there is an easy fix to the issue.

 

[Refueler]

Satellite requisition time.

It can take 20 mins to get a fix and I am usually well off the mooring in that time. As I pass through a busy military port, Plymouth, there is a lot of shipping and I like to be 'electronically' waving at everybody. Longroom (VTS) can also see me.

Out of interest - What GPS and AIS units are you using ? Maybe there's an answer to this 20min syndrome ?

 

[Refueler]

Just check that anything that you buy has a non-violate memory and an internal battery.

Given the design life and development time all 'modern kit' must be well over over 10 years old.

Both the AIS and VHF have been on the boat for over 10 years, but I really don't want to replace them as they will outlast me. It would be a complete waste of beer tokens and environmentally unsound when there is an easy fix to the issue.

Think you mean "non-volatile" memory ....

A GPS needs that to be able to work ... as it must have the data held in its memory .... remember the GPS roll-over ? That was when it really showed its 'teeth' !

 

[wonkywinch]

the only time extended time to fix is if you moved more than a reasonable distance from last known switch off

I notice that when I take my Tom Tom sat nav with me on holidays to USA and South America (worldwide maps on it). When I get home it takes an age to relocate itself as it must be doing long hand calculations to work out it's position vs "I've woken up again, last time I was in this position, so I must be in the same place".

It's possible the device has a CR2032 battery in it similar to a PC that has one to keep the BIOS ticking over. If the battery has died, that might account for the slow boot times. Again, make & model might have the smart people here find the answer.

 

[Sandy]

Out of interest - What GPS and AIS units are you using ? Maybe there's an answer to this 20min syndrome ?

I really don't have an issue with the '20 min syndrome' as I have a solution. I am pretty sure that the reason that the initial fix is not instant is I use the internal antenna on both bits of kit, as I said in a previous post I am not a fan of loads of antenna doing their best to make the boat look like a hedgehog and get in the way. You will have seen the amount of ironwork, some of Mr Brunel's finest, that is just to to the north of the mooring in post #31 that 'might' have an impact on getting a good initial fix and as Plymouth is a military port who knows what they might be doing with electronic countermeasures at anytime? If I was concerned I'd make a brew before setting off, it is just nice to know what big stuff is moving about, especially if it is military and avoid the 'men in black' asking you nicely, but firmly to move out of the way.

My ancient Garmin chart plotter is situated in the cockpit and gets a fix by the time I get back to the wheel from letting go of the mooring lines- it is not as if I struggle navigating my way down the Tamar out to Plymouth Sound as I still use things like charts, 2B pencils, a Breton plotter and an eraser.

The kit works once an initial fix has been acquired. On trips nether is switched off as it allows family and friends to either know where I am, or more pleasantly meet up for a beer. To date My longest longest passage was was six weeks and both worked flawlessly 24/7.

But for what it is worth:

• Standard Horizon GX1700E
• VespaMarine AIS Watchmate

 

[PaulRainbow]

But for what it is worth:

• Standard Horizon GX1700E
• VespaMarine AIS Watchmate

The VHF should take seconds to get a fix Sandy, i'm sure. Worth a quick email to the very helpful SH people.

I would also expect the Vespa to as well, might be worth an email to them too.

 

[wonkywinch]

Sandy, I just had a quick look at your GX1700 manual online. Perhaps when it's next acquired it's position, go into the GPS status page (page 20 of the manual linked below) and see how many satellites it can see.

From the same page, it looks like your early device doesn't contain a lookup table as it says "When the GX1700 is first turned on, it may take several minutes to compute a fix of your position. This is normal as the GX1700 is downloading 'alamanac' information from the GPS satellites".

https://standardhorizon.co.uk/wp-content/uploads/2019/08/GX1600_GX1700_OM_USA_EM048N161_5292013.pdf

 

[Sandy]

The VHF should take seconds to get a fix Sandy, i'm sure. Worth a quick email to the very helpful SH people.

I would also expect the Vespa to as well, might be worth an email to them too.

The VHF has never been 'quick' and I am sure it is because it is by the nav station.

I think Vespa have been taken over by Garmin and the model is discontinued, while I've had fantastic service from Vespa in the past it is not the end of the world if it takes time to build its tables.

As I said I'm not that fussed as I've got an easy fix as I do need to keep the Navtex powered up and it is just a matter of moving a wire a maximum of 20 mm.