Underwater GPS

[kayakdiver]

I'm the author of the deploy and recover method mentioned above...the msn group no longer exists...check out the video on Youtube by searching, "underwater gps". It shows a new adaptation of the original method.

 

[kayakdiver]

*The MSN group listed above no longer exists...check out my video on Youtube by searching "underwater gps" -- a low-tech solution...

 

[kayakdiver]

The top link on the above post is my article from Divespots.com...also published twice in Underwater Magazine. Search Youtube: "underwater gps" - to see a video of my latest application of this 10 year project (no predictable data cable / ext. antenna)
Mark, Marathon FL Keys

 

[mikesugar]

Why do you need to pull the floating GPS down? I would think the best thing is to just float it at the surface and let it record your track. Most garming handhelds can go down to a track point every 10 seconds. Then match the GPS coordinates with your dive computer data and your photos. Just make sure all the clocks are synchronized.

 

[sgl308]

Well... I'm no military expert, but wouldn't something like that be top secret? If there was one?

I can neither confirm, nor deny, but when I got out in 2004, they did not have a gps that worked underwater. We had to surface to get gps coordinates. Underwater we used a nav system that runs off a gyroscope. It senses the movement and direction of movement made by the boat and tracks the boats direction that way. It's very accurate, but we did surface occasionally to get an updated gps fix.

What is possible is for someone to make a gps-specific housing that has a port for an external antena, kinda like the ports for external flashes on the high end camera housings. The antena can then be a "floating wire" or just run up to the dive flag in tow. Maybe integrate it into a reel... But what do I know.

 

[JollyWaffl]

What is possible is for someone to make a gps-specific housing that has a port for an external antena, kinda like the ports for external flashes on the high end camera housings. The antena can then be a "floating wire" or just run up to the dive flag in tow. Maybe integrate it into a reel... But what do I know.

Possible, but one problem - you'll be measuring the position of the antenna, not the receiver. 30 m of high quality antenna cable isn't cheap either.