gpsdiver

*(Note to self: A surplus of "zeal" often leads to poor communication) Anyway... this thing sometimes is more of an excercise in communication than anything else. I've always noticed that I learn something from these kind of posts...but it can be repetetive. **regarding buoyancy...the housing that I use takes 2 lbs. to make it negative. I don't even bother to weight it anymore...just secure it to my BCD...thanks. **I have sometimes gotten comments about the fact that "mine already floats" etc. That probably won't help in this case because I'm taking the unit underwater and the switches would become compressed...I can't imagine that the salt water would do it any good either. Here's an odd fact about deploying the unit to the surface in a housing. I've noticed that when the GPS floats in a flat position...it doesn't seem to lose signal strength nearly as much as when held flat on land (surrounded by air....not water) I can't weight the container to make the GPS point up, as even a small amount of water coverage (at bottom of GPS) causes signal loss. *Scuba Geocaching? Maybe some avid cacher out there will run with this concept and get a nice U/W geocahing group going. (beach diving would be fun) I noticed that orienteering is big in Europe. Fort Lauderdale has some great beach diving areas, but I now live in the Keys (very, very little beach dive potential) I know that some caches are already place in water...but how about making a day of it? A veritable beach diving/ geocaching bonanza! *Safety first please! I will attempt to find a reasonable location for a sub-marine cache in the near future...it would be interesting to see how long it takes for it to be recovered. Thanks

Let me try describing what a typical dive with GPS might be like. **Note: Their is more than one method possible for the "deployment and recovery" of the housing. In this description I will only describe a method that works in tandem with a dive flag. I arrive by small boat at a familiear dive site. My Magellan hand-held unit has led the way. quickly dropping, I prepare to dive. The depth will be about 35 feet. As I prepare my gear, I notice that the boat has swung about the anchor, and seems to have settled nicely into the current. I easily "mark" this point by holding the go to button down for 2 seconds...then pressing enter. (Magellan Map/Pro). I place the GPS into a small, clear housing. The housing is fitted with 2 brass rings, and clips securel to my BCD. I prepare my simple dive flag for the journey also. This is not a typical ball type flag (too much "drag" in wind/current)...this is a flag made from a sausage-shaped boat fender...the kind you see hanging over the side of a boat. Two large plastic cable-ties hold a 3 lb. dive weight at the bottom-center of the float....a plastic flag with a wooden shaft is mounted at one end...while the tow line is at the other. I begin the dive, pulling the flag as I go. Although the wind is considerable, I scarcely feel a tug on the flag. About fifteen minutes into the dive, I encounter a huge brain coral, positioned next to a small, but healthy patch reef. I decide to "mark" this position. I simply take the line in my hand that pulls the flag....attach it to the GPS housing (with a brass pin-clip)..."drop" the housing...allowing the line to slip through my fingers as the housing rockets toward the surface. It is obvious when the housing hits the surface because the tension on the line suddenly releases...I can even see the housing, almost directly overhead. I don't simply sit motionless as I wait for signal to acquire...I enjoy swimming slowly around the impressive coral head...amazed at how many lobsters reside there. I wait a minimum of 60 seconds...then reach up, pulling down on the line in a hand-over-hand fashion, the housing reaches my hands quickly, as the flag takes up the created slack line. I make note of the lat./long. (either by switch, or by annotation...depending on whether housing has switches or not). The "go to" that is displayed shows that the boat is at bearing 130.... 175 yards. I continue diving for another 30 minutes, and decide to head back to the boat. I repeat the deploy and recover cycle and find that the boat is at 187...230 yds. (*I do not rely soley on the GPS, but try to keep an awareness of the boat's relative position by traditional techinques also). I begin swimming on heading (187)...I'm holding the GPS housing with an extended right arm, making use of a compass that is mounted at the top of the housing. After several minutes I begin to notice familiar topography. I also notice that I'm at a depth of 33 ft. (the depth where the boat is anchored). Just as I begin to wonder if I've swum to far, I see the distant anchor line, stretched at an angle across the ocean before me. Before ascending I deploy and recover the GPS one last time. I'm just curious about the relative position to a few spots in the area. I could do this in the boat, but it's fun to have the capability underwater. My housing has switches, so I go the the "user waypoint" area, and begin scrolling down through the list. As each waypoint is highlighted, the bearing and distance to each is shown at the bottom of the display. Wow! I'm only 620 yards from Milton Reef?...I thought it was further than that. I notice that I'm at 083... and about 5 miles from my house (useless but rather amusing info.). Another dive is complete. Another rare dive, making use of GPS data. http://groups.msn.com/divergps MSN group site on this topic

This conversation has go unbelievable legs to it. The best idea by far is to put a note in it telling the person to contact you and say what was in it (for return). It's good to see that people are concerned about doing the right thing, but as someone who has...shall we say...been exposed to "varying socioeconomic demographics"..."on the street" (so to speak)...this conversation would have never gone this far. The comment someone made about an arrest for turning in a stolen credit card was interesting. That kind of rediculous thing does happen rarely, and discourages people from trying to do the right thing. I saw someone on "COPS" get arrested for calling the police because they found drugs belonging to their teen son...how rediculous! On another episode the cops seized a truck that had a small amount of drugs in it. The problem? The vehicle had been reported stolen...and the thief was in the truck when they found the drugs! *It's a shame that in "the land of the free" it seems that we have turned into a land of fear and paranoia at times. Americans have never been more fearful, and more "risk averse" than now.

I had a weird experience like this while serving in the Foreign Legion(no I'm not joking...no, not a good idea) One of the corporals found about $240 in 20s in a brick wall. He confronted me and asked if it was mine (a good assumption, since I was the only Yank there at the time). I assured him that it wasn't mine, and he gladly kept the cash. It probably was some "escape" cash that a previous American had stashed.

sorry again...got a warning that "dynamic pages" are not allowed??? can't load the photo...but again....are viewable at http://groups.msn.com/divergps

Error loading image....will try later.

I've got some photos at my MSN group at: http://groups.msn.com/divergps Now let me make this next statement without sounding like a know it all. I kind of feel that I'm past the testing phase of this concept. It's something I've been doing for several years...am beginning training with law enforcement...have been invited to author a certification program for a major diving certification agency. **I'm mentioning this not to "blow my own horn"...but to illustrate the fact that this concept has been largely accepted by those who have tried it. Thanks

Well...that is the theory that the Garmin Corporation seems to go by. It seems that most of their units overwrite with some sort of "signal lost" message...disallowing the viewing of data...that is without signal. For this application it is kind of dumb luck that Magellan does not obscure the data. I do understand what your saying, however. All of the GPS manufacturers are careful to have disclaimers about using GPS as a sole means of navigation. I'm glad that I did have several hundred beach dives to learn to navigate, before ever using gps in this "deploy and recover" mode. The reality is that most divers don't dive often enough to even consider going to the trouble to try this. That's why my focus has been more towards working, and law enforcement divers. However, a diver that happens to also be a geocacher...seems to be a good candidate for the idea. My first exposure to GPS was in the USN, in '79. I think we got an update about once per hour.

HOW ABOUT A CHAT TONIGHT!! I will be at my MSN group site tonight at 8:30 p.m. (Fla. Keys) to chat about this concept. The MSN groups, require that you "join" in order to use the chat feature...so arrive a bit early to set-up. The group settings will give you the option of not receiveing emails, so don't worry about getting spammed. An MSN prompt will also appear asking you to load the chat software if you don't aleready have it...you know...the "do you see the smiley face" thing? The whole process is very quickly completed. Thanks http://groups.msn.com/divergps then click on the "chat" link on left side *p.s. These MSN groups are a nice way to set up a simple and free web site

I'll try to answer some of the questions of the last few posts, based on my experience with the "deploy and recover" method. 1) Question about whether the go to data can be used after loss of signal. The Magellan models(unlike many others)...will continue to display data based on the last acquired signal...in spite of the fact that signal is lost (as when pulling the unit below). This means that A) If I have customized the position screen to display "bearing" and "distance"...I can display 1 go to on that screen. With the addition of housing switches...I can scroll through a list of user waypoints, as the bearing and distance to each appears at the bottom of the display. 2)*statement that ALL containers may leak: perhaps true, but this has not stopped divers from taking expensive cameras underwater for decades 3) Statement about the effects of deploying and recovering a "buoyant" object (the container). The lift is so slight (can be made negative with only 2 lbs)...that this has never...ever been a factor at all. 4) statement that there is no way to record a go to electronically if GPS is in a rigid container. Method A) diver jots down data on slate...enters into gps post-diver Metghod *(housing with switches) diver uses 1 or 2 switches 2 "mark"... makes note of what 01...02...03, represent...and gives a name post-dive 5) suggestion regarding not knowing if the gps has acquired signal. This is a valid point, but one that can be addressed... **Important: if practicing on land(by covering/uncovering antenna with foil...it can often seem that the unit regains signal remarkably quickly. This, however, is only true if the unit has lost signal for around 4 minutes or less. In actual use...it is very, very important to allow the unit to surface for a minimum of 60 seconds (to reacquire from a "cold start") The diver may leave the unit on the surface for longer periods of time ***Imprtant: Diving at relatively shallow depth...want to have signal available to you in about 4 seconds? The unit can be "towed"...leaving it on the surface...when gps data is needed ....quickly pull down...view data...release...swim to next objective. **I want to be very, very careful not to sound like "Mr. GPS" here, but I would like for you to know that I have spent countless hours with this concept, both in the water and out. I promise you that this is not a gheory...this is a very usable concept. If you have a Magellan unit (particularly...Sportrak...Sportrak Map/Pro..Meridian) ...take it for a spin on land. Just use foil to cover and uncover the antenna as you walk about a testing area. **It is important to be skeptical... but please be careful not to look for a reason that the concept won't work. In testing...I've tried to create situations to "make" the concept not work...to make it fail, and have been surprised at the results. Why do I care? Because I am a great fan of diving...but I feel that the industry is very slow to change (case in point...the Nitrox debate of a few yrs. back) I know that a new concept will only be used, as divers begin to see other divers using the concept with good results. The objections that I often hear are very valuable to me...these help me to remember to address these issues when writing about the subject, or when speaking to a group. * One of the most amusing responses, came from a guy who angrily emailed me to tell me that the idea would not work. Why? His dive areas are covered with Kelp! I hadn't thought of that one, but in his world...very valid point. Thanks

Thanks for being a good sport about the whole thing. I think it has gotten easier to describe the concept as I've found out what the usual reactions...questions...and objections are. Thanks!!

Thanks for the friendly reply. One of the amazing things about this, is the low cost of the housing (by the way...I'm not selling them) I use the Otterbox 9000 "clear" model. It retails for between $10 to $20 dollars, and is rated to 100 feet. This might be a great general purpose cache container also. The best price that I've found is at aaacamera.com ($9.69). Be sure to get the "clear" model if using for "diver gps." I don't think there's enough market available to manufacture a profitable model. I simply take the above mentioned container...and send it to a housing manufacturer(along with the gps)...to have the switches installed. The installation was around $100...seems expensive, but is well worth it. **Without the switches you can view lat./long.- time - and a single "go to" all on one screen (Magellan sportrak, sportrak Map, Meridian....must customize the position screen to display "bearing" and "distance"...(refers to a "go to") In this application...you deploy and recover the unit...make note of any lat/long to be saved....and enter manually post-dive. (while also having the bonus of viewing the "go to" back to boat, start point , etc.) **Got Switches? By adding switches you gain 2 added functions: 1) the ability to press 1 or two buttons to "mark" an area(marks area of last deployment). 2)**This is a big one...based on only 1 deployment and recovery cycle...you can scroll through a vast list of user waypoints...making note of the bearing and distance to each! Most people won't need this, but it's a great feature for avid divers or research types. You can view photos at my informal site at: http://groups.msn.com/divergps (enter as shown...no "www") The funny thing? Although I love this concept, I would never invest a great deal of money in it. It is far too difficult to get people to try something different...and it's kind of a niche application. I think it is of note, however, if you consider the fact the underwater GPS use is very rare. I'm starting with the assumption that a diver does not want to bother with expensive or complicated equipment. Thanks for your interest. The internet is amazing in that it allows for the sharing of these kinds of topics with people we've never met. I've made some very, very important contacts this way.

I forgot someting! To the above person who was so critical of my "diver gps" posts...I propose a challenge. (All done in fun... a good natured challenge) I propose that you post your proposal for the best method for using GPS data underwater while diving. Not simply a theory...but something that a diver can truly use. I will then describe my method in exacting detail also. *This will not be about the future...it will be about now...what can we do now. Again...this is not intended to be a mean spirited sort of competition. You simply spell out your best suggestion...and I will spell out the details of a method that I've been using for about 3 1/2 years. Now....if you don't agree...please avoid any predictable or angry response. Controversy is a natural thing when it comes to talking about new ideas and concepts. YES! YOU HAVE BEEN CHALLENGED! *hey...this could be fun!!

Can you please give direct examples of how I am being so rude to others? That was not my intention. I was simply trying to stimulate others to steer away from the predictable direction of this topic. I did not at all intend to be condescending in doing so. Your repsonse however...is intended solely to be insulting and rude. The absoloute simplicity of the concept is the point. There is no intent to portry it a some astounding scientific device. In fact...the odd fact is that the "research" that you refer to...has not given much to the average research or recreational diver. It is very, very difficult for people to consider trying something that they have not seen in widespread use. I think that if you will look over my posts, you will find that your response is very exaggerated. It's odd that you acuse me of a form of rudeness, while your response is completely over the top. I will try to avoid sounding "preachy" in spite of the fact that, yes...these conversations always do gravitate toward predictable outcomes. You, however...may want to avoid being purposely insulting. These also is a predictable reaction from a very small minority of respondants....any time that a new avenue of thought or tactic is proposed. You many very well be a diving "expet" and that can sometimes be where the problem begins. Experts in a given field, are often hesitant to listen to the advice of others. Again...this is not about amazingly impressive equipment or concepts. It is about taking advantage of the height of simplicity in fact. Your reaction at theis point may be to: 1) Rail against me even more loudly than before 2) perhaps respond by saying something like..."Hey...maybe I did overstate my case...sorry." Again...I will try to avoid soundy "preachy" which is easy to do in this format. A final thought... Did you hear the story of NASAs past attempt to develop a pen that would write upside down...that would write in zero gravity? Supposedly, an Astronaut discussed this with a Soviet Cosmonaut, who is said to have replied, "Oh...we just use a pencil." My concept is the "pencil." My concept is the minimalist's approach. A ran into a guy who had a similar reaction to yours (he was an N.E.D.U.)diver...he railed about the great expense and complexity of the fantastic system of "diver gps" that his unit used. He failed to understand that the complexity of set-up...expense....and lack of practicality in the real world was not something that would benefit most research or civilian divers. I have no doubt that you are an expert of the highest degree...otherwise you would have no reason to react with such anger toward my simple approach. Now......play nice!!

You should see the looks that I get when I'm walking about in a park...covering and uncovering the antenna of my Magellan with a piece of foil. I do this to simulate signal loss, as when diving to test my "deploy and recover" method. I sometimes have cars that drive by slowly, or even double back for a second look. What about people that are afraid to fly? Even after a terrorist event this fear is rediculous...and it hurts our economy. People are quite fearful and "risk averse" in the more "sheltered" portions of our society.

One great disadvantage of this method, is that you only gain the GPS data after the dive. Using the "deploy and recover" method that I've described, allows for data use both during, and after the dive. Yes it can be helpful for geocaching, but I'd suggest that the avid diver might want to take advantage of the full capabilities of gps.

If you're not an avid diver...this wont interest you. My self-published book/user manual is available.... Underwater GPS: a practical approach The book form is $18.50 CD is $9 For more details you can always see the items on ebay under "underwater gps" or "diving compass" I'd be glad to answer questions, but please view the ebay description to clarify first. Thanks *(this concept is tailored for use with a Magellan unit) NO data cable/ floating antenna needed! *Note: this is not a theory...this is a working concept that I have been using for over 3 yrs. Easy to learn........Easy to use

I should add that in reading the guidelines...I see that any mention of sales of items should be restricted to the garage sale area. I should have been aware of this, and will be sure to follow that guideline in the furure......thanks

I have been "ungeocached" by a member it seems. Yes...I would be classified more as a diver than a geocacher. Diving and geocaching don't always go together...but for those who dive it is an interesting topic. Regarding ebay...yes I do have products on ebay, but you can be certain that I've spent more promoting the diver gps concept, than I've ever received from any sales. I end up using the small profits for printing costs for products that I distribute free of charge to various agencies involved in research and training. There is a natural tendency towared skepticisim when someone begins discussion of a topic like this. The reality is that only a small percentage of readers will have an actual use for the application. Let me answer a few of the above questions *Buoyancy: The housing can be made slightly negative with the additon of 2 lbs of lead....I've found that I prefer to securely attach the item, and skip the use of the lead. *Switches: The diver can observe 1 go to...and retain the ability to "mark" locations without switches *I have added switches(by sending the unit to a housing manufacturer) As mentioned in a previous post...this adds the ability to scroll through a list of user waypoints, observing the bearing and distance to each (based on only 1 deployment/recovery. **Important: The evolution of a topic like this is very, very predictable. Someone always (without fail) steers the topic toward a predictable method involving the use of a data cable/ floating antenna. **That's fine for the rare person willing to do so....this concept is intended to allow the diver to dive as normal...without cumbersome gear or pre-dive set-up. **someone mentioned the concept involving a floating unit, and the downloading of the track post-dive. This also has been done, and may be effective for some. My concept, however is more of a real-time operation....allowing for the use of GPS data during an ongoing dive. **Again... if some feel that this is "off topic" for geocacing...for most this is probably true. However, for someone who is both an avid diver, and a geocacher, this may open up new avenues. **Keep in mind that very, very few people in the world have ever used GPS data underwater. This concept allows GPS data to be used with only a housing and a Magellan hand-held unit. ***If you have a Magellan hand-held...give the concept a try on land. How? simply use alluminum foil to obscure the antenna area(to simulate submerged periods) ...walk about simulating the start of the dive, and the deployment and recovery(remove and replace foil) The concept is easily learned and proven on land. **Again...this topic will always....always...return to the discussion of the data cable/antenna rig. You can be certain that it is difficult to encourage a diver to try anything that's not been commonly seen in use...getting someone to use one of those type rigs would truly be a tough sale. *There is also an interesting psychology that follows this type of topic. Humans are so naturally skeptical that someone with a strong voice of skepticism will join the fray, without having seen...or having tried the method. If anyone reading this is a journalist(who happens to be coming to the Fla. Keys soon) I'd be happy to demonstrate and prove the method. The real "profit" that I've receive from promoting this concept is in finding some very interesting contacts within the diving industry who are helping to promote the concept. I can accomplish very little on my own. **Now...watch carefully as this topic will certainly swing toward the cable/floating antenna arrangement. Oh well.....

These are some valuable, and often heard points to consider. I don't have a problem with the unit drifting to a distant location...the unity deploys very rapidly...it is very, very obvious when the unit hits the surface(even in poor vis) because the diver suddenly feels a lack of tension on the line. Regarding your comparison to simply making a "mark" just prior to submerging...this is used at any time during a dive....only "as needed". Divers often need to avoid surfacing...even at a depth of 25 ft. or so, I truly do not want to surface until the end of the dive. Type of line? I've been using a kind of tangle resistant crab trap line (fm. Kmart of all places). I'm thinking about trying "running rigging" line as use in sailing applications...very thin, yet strong. **Note: Most of the applications in this concept can be done without switches in the housing. I've added switches to a housing which gives me the astounding ability to scroll through a list of waypoints...instantly viewing the bearing and distance to each (at bottom of display). **(all based on a single deployment/recovery of the unit) This data has proven to be as accurate as "go to" data. (I often display a primary go to on the lat./long. screen...by changing the default setting....to display "bearing" and distance" (which in this case refers to go to data....back to boat, etc.) *This concept is intended for avid divers and research divers...it is not a theory...it is an application that I've used on scores of dives with great accuracy. The concept can be learned on land by covering the antenna with alluminum foil (to simulate signal loss when submerged) I'm currently writing a second feature article on this concept...co-authoring a specialty course (at the invitation of a major certification agency) I will be starting the first training cycle with this "diver gps" with a group of public safety divers in a few weeks. **This is a "niche" subject that is not likely to put too many $$ in my pocket, but it is interesting to endeavor to add to the methods used in scuba navigation. It is simple, but without a certain level of promotion and training, it cannot make it into the diving community. Thanks

SCUBA DIVING WITH GPS: I'm using GPS data underwater...and no I'm not going to tow around some floating antenna attached to a cable. I gain GPS data...only "as needed" for the purpose of "marking" a position...or "keeping an eye" on the boat or other objective. I do this using a magellan hand-held unit. The method requires no elaborate pre-dive set-up, or equipment. It is a "deploy and recover" method, whereby the GPS (in a clear housing)...is "dropped" (while attached to a line)....ascends rapidly (positively buoyant)....gains signal....is pulled back below to find that the data is still displayed on-screen. Question: On deployment...doesn't the housing drift to a distant location, rendering the data innacurate? NO... the housing ascends quickly, and the diver limits the amount of line that is playe out. Question: Wouldn't it be better to attach some kind of cable thingy to a GPS that's affixed to a float, or somehin'? NO.... I like most divers, have no desire to tow around a cable/antenna arrangement. This project has been primarily an academic project...not a financial one. **Important: preconceived ideas are natural, and common regarding this subject. The simplicity of the concept can be deceiving...it is an astoundingly effective method. thanks