Handheld Garmin GPS as a dive accessory?

[rdharbis1]

I would like find a way to take my GPS diving with me. I use it all the time for navigating when I am fishing and I think that it would be really handy if/when I dive the river with the limited viz, or anywhere else that you may want to find your way back to an anchor line or some other entry point. :06:
Has anyone used the Pelican cases for something like this?
Are there other cases, devices, stuff.

 

[herman]

Keep in mind you will have to install an external antenna and have it floating on the surface before the GPS will recieve enough signal to be of any use. GPS's will not work under more than a few inches of water at best. Your best bet is to learn to navigate using your compass and the natural reference points around you.

 

[Sharkbait]

I would like find a way to take my GPS diving with me. I use it all the time for navigating when I am fishing and I think that it would be really handy if/when I dive the river with the limited viz, or anywhere else that you may want to find your way back to an anchor line or some other entry point. :06:
Has anyone used the Pelican cases for something like this?
Are there other cases, devices, stuff.

Due to the operating frequency of GPS the signal won't penetrate water, or dense folage for that matter.

Sorry to say, but GPS (in it's current state) won't work underwater.

 

[O2BBubbleFree]

Hi there, rdharbis1.

There have been several discussions on this subject on the 'board. In summary, GPS signals are too weak to penetrate the water, so the receiver will not work underwater.

Other locating technology exists for use underwater, but it's cost prohibitive for us amatuer divers.

There are ways that you can put your GPS in a float, and mark sites while towing the float, but marking a site accurately is going to be a problem. The big issue is keeping the float directly above you.

Further info can be found by searching the site, however from what I understand the search engine requires at least four letters, so you might try 'GPS*' or '*GPS' or '*gps*'.

 

[rdharbis1]

Hi all,
Well, I thought it would be a good idea. I shold have searched the board first but then no one would have had a chance to steer me in the right direction. I ma still learning - this board and diving - and both are fun!

Thanks,
rdh

 

[steve1508]

Hey, I'm with you. Somebody has to figure it out, if for no other reason than the challenge. I just posted a question similar to yours and I guess I should have searched the Forum, also. I'm tempted to build my own prototype and give it a shot. You can't beat the "back-track" feature of a GPS unit. But what do I know.

 

[steve1508]

By the way, what model Garmin are you talking about? I have a GPS V with a detachable antenna that makes the job a little easier.

 

[Cacia]

I love that Garmin 305 for bicycles...it has the maps and everything. The cool thing is that it snaps off and can go other places. Also, has amazing training programs.

 

[mike_s]

While I agree with the others, it's hard to do GPS underwater, check these out. The 1.5ghz wavelength of GPS signals just doesn't penetrate the water.


http://www.underwater-gps.com/ But I don't think it's going to be in a price range for the recreational diver.


Also The Node Explorer: An Underwater GPS
http://www.divester.com/2007/01/05/the-node-explorer-an-underwater-gps/
or
http://www.nodeexplore.com/hardware_nodeexplorer.shtml


This Scubaboard thread also references a free GPS Diver book you can download
http://www.scubaboard.com/showpost.php?p=1840593&postcount=9

Book:Underwater GPS: A practical Approach
http://wl.filegenie.com/~8675309/UW_GPS_Book.pdf



Have Fun.

 

[The Kraken]

How about this?
Put the hand held GPS in a waterproof, positively buoyant case similar to an Ikelite.
Tow it on a reel.
When you want to mark a point, slowly take the slack from the reel line; this will place the GPS directly overhead.
Pull the GPS down and record the current co-ordinate.

the K-ompass