Danny_Labrador
Well-Known Member
Can anyone help me here please. Do any of the hand held GPS devices have an anchor watch facility or do you need to buy really expensive gear ?
GPS anchor watch
- Thread starter Danny_Labrador
- Start date
Beagle
Well-Known Member
The models I'm familair with (Garmin, Magellan, Furuno) all have that s a standard feature. I think any modern model you can buy has it.
Pretty easy to check once you set your mind on a certain thingy....
Pretty easy to check once you set your mind on a certain thingy....
fireball
Well-Known Member
The basic Etrex that I have doesn't have anchor watch ... the other "more marine" type ones may do though.
Joe_Cole
Well-Known Member
My Garmin does, but my MLR handheld doesn't.
I don't use it though. I've found that it's either too sensitive and just swinging on the tide sets it off, or it's not sensitive enough and I'ld have hit the rocks before I had time to do anything!
I don't use it though. I've found that it's either too sensitive and just swinging on the tide sets it off, or it's not sensitive enough and I'ld have hit the rocks before I had time to do anything!
starboard
Well-Known Member
Surely you can adjust the range at which it goes off. I find if I set the alarm to 0.03nm that is about right on my Furuno.
Joe_Cole
Well-Known Member
Yes, I can alter the settings. It's just that whatever setting I tried, it ended up being either too sensitive or too insensitive! To be honest I only tried it a few times before I lost confidence in it. I got fed up with false alarms in the middle of the night so now I just let out a little more scope if in doubt! The alarms may be fine, I just couldn't get on with them.
G
Guest
Guest
Best is to use the pc version - then what ever gps you have doesn't limit you on swing diameter ....
Setting anchor watch on Maptech etc. - much better and more controllable.
Setting anchor watch on Maptech etc. - much better and more controllable.
[ QUOTE ]
Best is to use the pc version - then what ever gps you have doesn't limit you on swing diameter
[/ QUOTE ]
Does this mean some PC chartplotters allow an adhoc shaped boat movement boundary to be set?
Best is to use the pc version - then what ever gps you have doesn't limit you on swing diameter
[/ QUOTE ]
Does this mean some PC chartplotters allow an adhoc shaped boat movement boundary to be set?
Oldhand
Well-Known Member
Alright if you have a generator (to annoy the neighbouring boats with) but running a PC 24/7 for anchor watch would be a trifle battery hungry on most people's boats!
Whatever happened to taking bearings on landmarks, plotting the resultant position on a large scale chart and checking for any significant bearing change? To rely on a GPS, especially a hand held whose antenna is unlikely to have a clear view of the constellation is asking for false alarms. They in turn will tend to make the operator select a larger warning radius which is likely to make the alarm marginal for safety...
Whatever happened to taking bearings on landmarks, plotting the resultant position on a large scale chart and checking for any significant bearing change? To rely on a GPS, especially a hand held whose antenna is unlikely to have a clear view of the constellation is asking for false alarms. They in turn will tend to make the operator select a larger warning radius which is likely to make the alarm marginal for safety...
bedouin
Well-Known Member
I often thought that the correct way to do this is to set the anchor watch when you are directly over the anchor, and set the sensitivity to a bit more than the scope. That will enable you to swing without triggering the alarm, but will be sensitive enough to genuine dragging.
I can't say that I've ever tried putting it into practice - I prefer to use the depth sounder as the anchor alarm.
I can't say that I've ever tried putting it into practice - I prefer to use the depth sounder as the anchor alarm.
BrendanS
Well-Known Member
That is exactly what I do, minus a little to allow for scope not being a flat line, plus 15m to allow for GPS inaccuracies (which should decrease to 3-5m when Egnos finally goes on line)
Joe_Cole
Well-Known Member
I'm ashamed to admit that I've never thought of that. My only defence is that I've only played with it, I've never really used it in anger! /forums/images/graemlins/blush.gif /forums/images/graemlins/blush.gif /forums/images/graemlins/blush.gif
Ships_Cat
Well-Known Member
That is what we do too. The only tricky bit is rushing down to the chart table to hit the alarm when over the spot then getting the anchor on the bottom before getting blown/drifted off (we don't have a GPS repeater at the helm). We always anchor with a "cushion" between the guarded circle and any dangers.
We always rely on it and sleep soundly through the night unless the weather is so very heavy that the consequences of a drag outside of the guarded circle would be immediately serious. But have to say that in the 9-10 years we have been relying on the GPS we have never dragged (put down to "good luck" not good management by some posters /forums/images/graemlins/frown.gif), however we do get false alarms if the scope has taken us outside of the circle cos didn't set alarm directly over the anchor so do know it works.
Much better now that selective availability is turned off.
John
We always rely on it and sleep soundly through the night unless the weather is so very heavy that the consequences of a drag outside of the guarded circle would be immediately serious. But have to say that in the 9-10 years we have been relying on the GPS we have never dragged (put down to "good luck" not good management by some posters /forums/images/graemlins/frown.gif), however we do get false alarms if the scope has taken us outside of the circle cos didn't set alarm directly over the anchor so do know it works.
Much better now that selective availability is turned off.
John
BrendanS
Well-Known Member
That's the advantage of a small boat. I hit the button just as I cruise to a stop, then run up through windscreen and onto foredeck to let go anchor, then let go when stopped. Within a few metres, allowing for fact that scope is a diagonal of a triangle very roughly, and allowing for 15m gps accuracy, it works pretty well.
Any other settings than that will trigger the boat swinging if on a decent length of chain and or rode
Any other settings than that will trigger the boat swinging if on a decent length of chain and or rode
G
Guest
Guest
Maptech .... circle
Capn Voyager ....... irregular or circular area
others .... need to be checked out as to whether circle or shape ...
Capn Voyager ....... irregular or circular area
others .... need to be checked out as to whether circle or shape ...
colvic987
Well-Known Member
garmin 76 handheld has anchor alarm, check the manual from garmin site, you will need a pdf reader..
