Anchor Alarm

[lpdsn]

I've wired a latching relay and 90db piezzo sounder to our Garmin, can be heard anywhere on boat and keeps going until cancel button pressed.

Unfortunately, the 158 doesn't seem to have a suitable output. I can check next time I'm on the boat to see if there's anything they forgot to mention in the manual, but sounds like that idea is a non-starter. At least it was a good one.

 

[charles_reed]

As both Vic and I tend to anchor in the Med, where tidal flows are uncommon, we probably find GPS anchor alarms reasonably satisfactory in letting you know when you're wandering.
However I'd suggest it's far better to have an anchoring system and technique which have a very low failure probability.
Visual fixes are essential, but when you're setting the anchor - I used 2500r pm with an Autoprop for 60" minimum or until the boat starts to fishtail.
I do set the GPS alarm, usually with a 30m diameter, dependent on the scope (the boat is 10m from anchor chain to GPS receiver).
You do need an audible alarm - the really serious drags occur when you're asleep.
In the old days, GPS reception used to drop around dawn, leading (in the 70s & 60s) to many false alarms.
The max-min, depth alarm is so imprecise on most systems to lead, IMHO, to a sense of false security.

 

[lpdsn]

I only know Loch Ryan from the shore, but isn't there a tide to cause the boat to swing around thus interfering with a GPS position alert ?

If lying to all chain, you should be able to hear the groud tackle grumbling if dragging, especially if you're in a forepeak berth.

Maybe anchoring technique or the places one does it are more the questions.

Seriously Seajet, you seemingly don't even know how anchor alarms work. And because your idea is demonstrably not universally applicable you start trying to insult my anchoring skills and the places I visit. Somebody should invent a character like you and put them in a sitcom.

 

[AngusMcDoon]

In the old days, GPS reception used to drop around dawn, leading (in the 70s & 60s) to many false alarmsl.

The first operational satellite was launched in 89 so whatever you were using it wasn't GPS. Decca maybe, although was too expensive & physically hefty in the 60's for small craft.

 

[Seajet]

I know precisely how they work, which is why I question their effectiveness.

Doesn't it strike you, you apparently do a lot of anchor dragging ?

This was quite honestly meant as a serious point, NOT an insult and I apologise it came over that way.

So, maybe better to study why - either technique, tackle or the place/s chosen - than look to kit that might read to .00001 decimals on the screen but may not actually be that accurate - a lot of people fall for this with electronics - including depth sounders unless they spend time getting used to their kit.

I would be looking to other things than ' a better alarm when I drag '.

 

[AngusMcDoon]

I know precisely how they work, which is why I question their effectiveness.

So if the OP is anchored in The Wig in Loch Ryan, which is two thirds of a mile wide, & he sets a GPS anchor alarm to go off if he moves more than 50m, in what way is that ineffective?

 

[Seajet]

Twisting my words as usual.

I'm saying GPS alarms do not really work so accurately and specifically to a boat swinging around an anchor at a crowded anchorage; one can adjust the gain on depthsounders but with gps it requires a very long pole and strong arms.

In Loch Ryan, the question apparently is why drag if the seabed is so constant ?

 

[AngusMcDoon]

Twisting my words as usual.

I'm not twisting your words at all. You are harking back to crowded anchorages yet again as found in the limited south coast area that is all you seem to talk about & therefore I presume you have experience of. It's unusual to see 1 boat anchored overnight in Loch Ryan. Being so squashed in that they might swing or drag onto each other just never happens there, as is the case in most Scottish anchorages.

You really should expand your sailing horizons; you might learn something rather than being so stuck in your opinions and ways. Have you sailed anywhere at all this year?

 

[lpdsn]

Twisting my words as usual.

I'm saying GPS alarms do not really work so accurately and specifically to a boat swinging around an anchor at a crowded anchorage; one can adjust the gain on depthsounders but with gps it requires a very long pole and strong arms.

In Loch Ryan, the question apparently is why drag if the seabed is so constant ?

Look, let's start again. I want one solution that can be used anywhere, so thanks for your suggestion of the depth alarm but it doesn't do the job consistently enough. I can list a good number of anchorages where a boat could drift for a fair way, in fact could run into trouble, before a depth alarm would give any warning, especially when you consider it would have to be set to avoid false alarms because of the normal tidal range.

I know how to use an anchor alarm, I've used the old one and ones on OPBs boats for years. I can set the range on the alarm according to the circumstances. Apart from volume issues with the latest GPS I've had no problems with them.

I also know how to anchor so the fact I'm interested in a practical anchor alarm does not mean I'm going drag, it means that I consider it seamanlike to set an anchor alarm if going to sleep just in case.

 

[AngusMcDoon]

Well given that your GPS is not loud enough & doesn't have an output for an external alarm, your options are...

1) Change it, but big £
2) Use an additional handheld GPS with the correct functionality where you sleep
3) A smartphone and app for £50
4) Hack in to the electronics of your current GPS & take an output from the sounder & amplify it to drive a bigger sounder
5) Make something yourself using a small processor & software (which is what I have done).
6) Go and anchor in the Solent if you can find space & use multiple depth sounders

I can't think of any other solution.

 

[lpdsn]

Well given that your GPS is not loud enough & doesn't have an output for an external alarm, your options are...

1) Change it, but big £
2) Use an additional handheld GPS with the correct functionality where you sleep
3) A smartphone and app for £50
4) Hack in to the electronics of your current GPS & take an output from the sounder & amplify it to drive a bigger sounder
5) Make something yourself using a small processor & software (which is what I have done).
6) Go and anchor in the Solent if you can find space & use multiple depth sounders

I can't think of any other solution.

I think I'll probably try messing around with OpenCPN and plug ins. I was hoping someone might identify something else I could install on the tablet and connect up to the GPS via WiFi (vYacht) but if there's anything out there I guess forumites haven't spotted it - or if they did gave up on this thread a while back.

I've also still got the Garmin 128 which works and could fit that in my cabin, but getting an aerial connected to it could be awkward just because of the layout.

 

[AngusMcDoon]

I think I'll probably try messing around with OpenCPN and plug ins. I was hoping someone might identify something else I could install on the tablet and connect up to the GPS via WiFi (vYacht) but if there's anything out there I guess forumites haven't spotted it - or if they did gave up on this thread a while back.

I've also still got the Garmin 128 which works and could fit that in my cabin, but getting an aerial connected to it could be awkward just because of the layout.

I forgot about the OpenCPN option. If there's nothing available currently you can suggest it as a new feature.

 

[GHA]

I think I'll probably try messing around with OpenCPN and plug ins.

The watchdog plugin is very good, it ties in with another drawing plugin so you can specify an area and sound an alarm if the boat goes outside that area.
I use an android phone with anchor pro, it's fine as well and less power.

 

[Seajet]

I'm not twisting your words at all. You are harking back to crowded anchorages yet again as found in the limited south coast area that is all you seem to talk about & therefore I presume you have experience of. It's unusual to see 1 boat anchored overnight in Loch Ryan. Being so squashed in that they might swing or drag onto each other just never happens there, as is the case in most Scottish anchorages.

You really should expand your sailing horizons; you might learn something rather than being so stuck in your opinions and ways. Have you sailed anywhere at all this year?

For your bedroom wall montage about me as you seem so interested, my areas sailed

UK South , East, West coasts

Firth of Forth

Channel Islands

Cotentin Peninsula

North Brittany

Normandy

Burgundy

Lake District

Various UK inland lakes & reservoirs


and later today will hopefully be my first proper weekend sailing my boat this year as my 93 year old parents - and self - have been and continue to be seriously ill.

Up to now this season all I have done is the odd quick sail on mine and serious work and short sails on novice chum's boats - dinghies & cruisers - due to time pressure and having to trundle parents and / or self to and from various hospitals and doctors.

So to say I'm looking forward to later today is an understatement.

I dare say you'll turn that into a great lacking on my and my boat's part, but as I've had her for 38 years on and off and usually cover around 1,000 miles a season - or just on the 3 week cruises I used to be able to get away for - I don't give a toss.

 

[sailaboutvic]

Seajet , Angus .
Has I have said so many times in the past , anything to do with anchoring seen to bring out the worst in people .
You two need to give it a rest before one of you end up saying some thing and getting band .
As far as anchor Alarm goes , use what ever works for you . Just like anchors different circumstances means you need different equitment to do the job .
The op don't want to use an App , that fine , then he have to use some thing else that will do the job for him , personal I find app work very well in Tidal and non Tidal , I can set it where I want , enter my own Lat and long , extend the radial if need be even set mine to send me an SMS , although I not sure I want to be on a bus or half way up an hill and get a text saying my boat dragging .
best of all , if it goes off I don't need to get out of bed to see what's happening , like most thing at time they will go off for no reason .
It won't stop other boats swing or dragging into you , if you want that you need to set an radar alarm .
The op said he can't hear is Garmin , as he already has a tablet , for just a few pound as suggested he could try out a anchor watch app , there some good once about also some not so good . Try and error .
Some say they don't need an alarm as they never drag , I can only say you been very lucky and when the day comes that you do , you wish you has set one .
As for us we about to be hit with another Bora over the next few days wind forecasted over 40 kts , so we expecting gust well over 50 kt and more ,
I for one will be setting an anchor alarm ,
I like to get some sleep .

 

[AngusMcDoon]

As I have said so many times in the past , anything to do with anchoring seen to bring out the worst in people .
You two need to give it a rest before one of you end up saying some thing and getting band .

As for us we about to be hit with another Bora over the next few days wind forecasted over 40 kts , so we expecting gust well over 50 kt and more ,
I for one will be setting an anchor alarm ,
I like to get some sleep .

Oh it's only a bit of fun. Trouble with internet everywhere, whereas before on the dull bits on passage it meant reading a book, now we can while away the hours posting here.

40 knot Bora? Pah! You don't know your born! It will still be warm for you. We've got a F9 coming in at the weekend in Scotland. It will be cold, wet & howling for days. Anchor alarm? Sod that. I'm taking the nesh option & running off into a marina.

 

[RichardS]

As for us we about to be hit with another Bora over the next few days wind forecasted over 40 kts , so we expecting gust well over 50 kt and more ,

Sorry to hear that Vic and Chrissie. Make sure that Eddie is safely tucked away. Here's a photo of more gentle times:

I'm not sure what the original anchor watch question was but there are so many alternatives on tablet or laptop that I've lost count.

I use

OpenCPN built-in anchor watch on tablet using tablet GPS
OpenCPN anchor watch on tablet using GPS position received over wifi from boat system
OpenCPN anchor watch on laptop using GPS position received over wifi from boat system
Anchor Watch Pro app on tablet using tablet GPS
VesperMarine built-in anchor watch on tablet using XB8000 wifi GPS data
VesperMarine anchor watch on laptop using XB8000 wifi GPS data

etc, etc

Richard

 

[noelex]

An anchor alarm is the best crew member I have.

He sits watching my position the whole time, never goes to sleep, never gets distracted and is ready to jump up and down if I move much more than a boat length outside my swinging circle.

All he requires is about 4AHrs a day to keep him happy, although I have a sneaking suspicion when I not watching he might sneak some of my single malt .

It is sometimes claimed if you have good anchoring gear an alarm is not needed. I don't agree with this. Even excellent anchors can occasionally be defeated. There are diverse ways this can happen. Good anchoring practice such as setting the anchor also gives the anchor a test, but still is not foolproof.

Take this Delta for example. It has landed in a small area of smooth rock. The hold would have appeared very secure, but a slight change in direction of pull could well see the anchor drag rapidly.

There are many other examples of ways anchors can be disabled. What about debris ? There is unfortunately loads of natural and man made junk on the bottom. I photographed this towel a few days ago:

 

[AngusMcDoon]

That's an excellent, if somewhat worrying, picture. Thanks.

 

[sailaboutvic]

Sorry to hear that Vic and Chrissie. Make sure that Eddie is safely tucked away. Here's a photo of more gentle times:

I'm not sure what the original anchor watch question was but there are so many alternatives on tablet or laptop that I've lost count.

I use

OpenCPN built-in anchor watch on tablet using tablet GPS
OpenCPN anchor watch on tablet using GPS position received over wifi from boat system
OpenCPN anchor watch on laptop using GPS position received over wifi from boat system
Anchor Watch Pro app on tablet using tablet GPS
VesperMarine built-in anchor watch on tablet using XB8000 wifi GPS data
VesperMarine anchor watch on laptop using XB8000 wifi GPS data

etc, etc

Richard

Found an hole to tuck are selfs into so hopefully we just going to get the tail end maybe 40 / 50 plus ,
just a few miles north of us DHMZ are forecaster in 70 plus Kts with gust of over 80 plus Kts .
It's the claim before the storm at the moment F3 , 35c inside the boat .
Spending more time in the water then on the boat .
Nice photo Richard .