Sitting here in Zihuatanejo we have been playing with the anchor watch app on our Samsung galaxy tablet. The one we have is free but comes with a price :) The price being some things do not work. Like the "Reset" button or if the alarm goes off the stop button does not stop the alarm which is bells sounding. So that makes you wonder if the rest is OK. Do we bet our boat on this app?
We have been looking for others and may even pony up some pesos for one if we decide we like it.
I was looking for more anchoring apps for Samsung galaxy tablet and found this one -
'My Anchor Watch Free" mostly free (can be downloaded from Amazon). It has some interesting instructions about setting an anchor watch (although the numbers aren't explained) - e.g. in 30' of water with 90' of chain, the drift limit would be 140'. (All ratios I suppose so you could adjust accordingly for the actual.) They instruct that the watch is set as soon as you drop the anchor.
We currently are in 12 feet of water under the keel and so we add 6' of water to water line (we draw 5.5' plus all the stuff we loaded the boat down with) and the 6' to our bow roller so that makes 24' depth. We have 7.1 out so that is 150' of rode. Using their numbers we came up with 234' of drift for the alarm if the alarm was set with the tablet at the bow. That is using the 90:140 numbers from that app adjusted for our 24' depth and 7.1 scope.
Oooops .. I forgot the 2' tide change here. So add that to the depth of 24' and you get 26'. Any way you get the idea.
Now if the tablet is not on the bow when you do this, then you have to add the number of feet for where the tablet actually is. We haven't tried it yet and possibly will in Papanoa!
For us we would not put our Samsung galaxy tablet at the bow while anchoring as it can get like a fire drill at times :) and we do not want to lose the Samsung galaxy tablet! So Debbie would set it at the helm and then we would take into account the difference in feet from the hem to the bow as the GPS coordinance would be at the helm.
Then we can put our Samsung galaxy tablet 3 with it's 8" screen by our stateroom bed and it wakes us up no problem. Like I said before we used it two nights in a row and stil had 58 percent of the battery left. It charges up no problem from our solar power\inverter and so can go on and on. If we use our Garmin electronics\chart plotter it would draw a lot more and from our house batteries. Plus the alam is out in the cockpit.
Another benefit of the Samsung galaxy tablet is the compass app. You can keep an eye on the boats course with it from anywhere on board. So if the crew or autopilot mess up you know about it.
Of course some navigation apps would do this also.
Setting an anchor alarm is not for a lot of people; we, however, are full time liveaboards and cruisers. We go to a lot of new anchorages and some have hazords. In fact, we have re-anchored a half dozen times in our short stay here in Zihuatanejo, twice for fire works and then anchored back at our original way point as we knew it was a good spot. Makes it easy to anchor and that we like. Also if you lose the anchor you have a good idea where it is because you have a way point when you dropped it. If you come into an anchorage at night (we have not yet but possibly if we have been there before) that we have already been to we have a good way point in which to drop the hook, you know the beach can look mighty close or far away at night!
I have found that the Lewmar 8 plait anchor line while great to handle and work with has a splice that is too big for the gypsy, that was done by Rigworks in San Diego, Ca. That will be in another post.