Which watch ??? free dive+scuba+gps

There are many watches with Freedive/SCUBA modes (Aeris, Cressi Eddy, Suunto D4, Mares Nemo, etc). I have owned the D3 (lost it), and the Cressi Eddy II (currently own). I have never heard of one with GPS... That would be an awesome innovation - especially for spearfisherman. To mark fishing spots, I have toted my garmin (in a drybag), attached to my float.

Does anyone know if the connection between the GPS and the satellites work under water? If not, then I guess the best alternative is to have a separate GPS at the bouy so the GPS doesn't have to reaquire connection everytime you surface. If the connection does work under water, then someone should really have made better use of it before, getting 3d-dive profiles etc.

Chrillepille said:

Does anyone know if the connection between the GPS and the satellites work under water? If not, then I guess the best alternative is to have a separate GPS at the bouy so the GPS doesn't have to reaquire connection everytime you surface. If the connection does work under water, then someone should really have made better use of it before, getting 3d-dive profiles etc.

Click to expand...

GPS does not work underwater

cheers
dave
Spearguns by Spearo uk ltd finest supplier of speargun, monofins, speargun and freediving equipment

in a simple response yes a Freedive/Dive/GPS watch is a Pipe dream of Startreck Sci-Fi proportions. This is based mostly due to the propertys of Seawater, and the limited propagation of GPS Microwaves through the first 12 inches of water. Physics wont change in the future, so the evolving technology will have to. So far things are going to an acoustic subsea system similar to, and utilizing GPS locational awareness for military submarines. Consumers with GPS watches wont see anything practical for at least 5-10 years.

go buy a GPS and a Drybox for your Bouy, and use a good Freedive/Dive watch. later you can upload the data into Excl and chart it fairly nicely, but it will take some time, and data entry will most likely be manual not automated, unless you write a java application for dataentry into a GUI form that can chart using Excel mathematics.

I woud recommend Cressi EDY over the Suntoo D3 anyday due to the hardened mineral christal face of the EDY, and the N2 and O2 calculations employed by Cressi. I still have an EDY after 3 years of use, and the face is flawless.

best of luck.

TBGSUB.

tbgsub said:

in a simple response yes a Freedive/Dive/GPS watch is a Pipe dream of Startreck Sci-Fi proportions. This is based mostly due to the propertys of Seawater, and the limited propagation of GPS Microwaves through the first 12 inches of water. Physics wont change in the future, so the evolving technology will have to. So far things are going to an acoustic subsea system similar to, and utilizing GPS locational awareness for military submarines. Consumers with GPS watches wont see anything practical for at least 5-10 years.

Click to expand...

good summary

I thought there were programs out there that you could download to automate the data entry process for data obtained both from your GPS (I used to use Waypoint+ years ago) and your dive computer (not so sure about this..)?

EDY has a nice PC interface I have been using also for 3 years, but the tabular access may take some doing to export a table into a GPS dbs. someone would have to have written a Java or C++ app for the purpose. perhaps a scientist may have done so and provided a link to a free copy of the app, but doesnt that sound a little like wishing on a star?
I think it would be easier to open the text exported file, and cut paste it into excel.

Hey, just to chime in...
from what little I know of EM wave propogation, only HF (3-30 MHz) and lower will penetrate water. For more than ~20 m. you really need to be transmitting in LF (30 kHz-300 kHz) Military Subs do this but it will never be able to be put into a watch because the antenna needed to recieve these types of signals needs to be tens of meters longs. But maybe there will be some innovation in mini-antenna tech. using fractals?? But most likely it will never happen. You need to enter that data on the surface unfortunately.

i dont see why a remote transmitter mounted on a dive bouy cant be used so that the transmition from satiliateds to bouy is as standard and then a transmition from remote bouy antenna to watch?computer could be completed (20-30m) this would allow a relativly accurate fix. mind you i cant imagine myself laying on the bottom looking at my gps thinking now where did i mark that snapper spot???? but i dont see why it cant work would just mean you would have to tow a float bouy around (which alot of spearfisherman do anyway)just a thoughtDD

Lots of good dive watchs out there to choose from these days. Take a look through some of the threads on here to see which ones look interesting to you.

Another option on the GPS front is to get a new camera- I always like playing with cameras. Many of the new ones have GPS software built right into them. The first one that comes to mind is the new Nikon P6000. It's a compact with close to 14 megapixels and GPS software built into it. All you would need to do is surface from your dive and take a picture- lat/long is automatically saved with the image.

Since we are all talking about freediving on here there's not much need for underwater GPS. We have to come bakc up very few minutes anyways so marking a target on the surface isn't that difficult.

For underwater navigation, other than a compass, I used to use a DiveTracker underwater beacon system with my dive scooter when scuba diving on wrecks in bad vis. I could attach the transmitter below the boat and kept the receiver with me. At the end of the dive ti would direct me back to the boat. You just needed to be sure you mounted the transmitter below the thermocline or it would bounce signals all over the place- but not to you.

Submarines use something different to send signals while underwater. There's a special system called Extra Low Frequency (ELF) that send out signals world wide thorugh a huge antenna. The only reason I know anything about it is because the military used to have one of these antennas in the northern part of my state, and locals used to protest the signals coming off of it- something about messing with the cow's milk production. The antenna itself was set up in the shape of a giant "F" and was miles long in all directions.

I know that we get a lot of military toys to play with these days, like rebreathers, but I've never heard of a civilian version of this.

Jon

I'm not sure yet- I don't have one.

My father-in-law is in the process of getting this upgrade installed on his D300 and will tell me how it works when he does. With that camera it didn't come standard and he's hoping the upgrade arrives before his Roatan trip next month.

Jon