Gps???

[Murat]

Generally i dive from shore and i know some rocks thta might hold the fish, but sometimes i can not found those rocks if the visibility is poor etc.etc..

I wonder if a GPS will help me to found those rocks in water? I know they can be used for that purpose in boats but the models i am talking about is small and cheap ones like this [ame]http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5799369382&category=34289[/ame]

or smillar models. I don't need fancy expensive units. I will tie it to my float and pinpoint locations so i can find them easier and more efficiently later. Any idea or model that will fullfill my requirments?

 

[dave]

I would go for a garmin etrex, fairly cheap, small, pretty reliable. I am not too sure how waterproof they are though, I have never had any problems using one in a very wet boat, but it may not like being actually immersed in water for long periods.
For most stuff within swimming distance of the shore, transits can be just as accurate as a GPS. One good tip is to take photos of the transits and laminate them so you can have them on your float, as this is much better than trying to remember exactly where the funny shaped rock should be in relation to the tree etc
cheers
dave
www.spearo.co.uk

 

[Pablo FR]

I have a Magellan Sportrack Pro Marine GPS on my kayak. It is dead handy for finding places, especially when you've got the nautical charts on your PC. You can pinpoint interesting looking places on your PC before going out.

However, they are usually certified XP7 (or something like that) which means they are supposed to be water resistant at 1 meter for one hour. Don't even think about putting under water even for as long as 10 seconds. Not only do they stop functionning pretty quickly but also the battery area does not have to comply with the standards. Batteries don't work well in salty water.

Some use them on their float boards but only in a dry bag.

 

[Murat]

e-trx seems good very nice priced too, but in its describtion it says its waterproof and can withstand with accidental splash rofl rofl

It seems if i get one i should keep it on my float rather than tie it...

Dave, those rock-tree realitons don't work me as well, after going the spot next time i find out that all the rocks and trees seems smilar rofl. Anyway forgive my ignorance but what is that transit technique in detail? never heard that one bbefore :hmm

and is there anyplace that sells this etrex stuff in england?

does it have built in compass? or you should have seperate compass to find the point? I search for etrex and in the picture i found there is an arrow in the middle of the screen, i suppose thats showing the way to go to found the desired point...

 

[akrikel]

hey murat, i use a base model e-trek on my boat and it endures quite a bit of abuse. but thus far it's still rock solid! the battery compartment is definitly not water proof, in fact this is stated so in the manual. i bought mine in the us for $80 2 years ago, but the model u suggested would be a great option, with better wet proof and also WAAS accuracy enabled! should give you a 3 meter accuracry increase. there are only specific models which have electronic compasses, but all will display course. the arrow in the pic is a go-to-waypoint option which points in direction of travel. only works if unit is actually moving. hope that helps!

 

[dave]

Using transits involves lining up 2 points in one direction, and another 2 points in another direction, so that you have 2 imaginary lines which intersect at the point you want to find again. To navigate back to the point, it is normally easiest to line up one set of transits, then move along that line until the other set line up. For some spots, it can be easiest to have several sets of transits, some to get you in the general area (which use obvious landmarks) then other sets which enable you to pinpoint the spot.
Taking photos of the transits is very useful as it means you have a reference of what they look like, a drawing is also useful, but it is very difficult to sketch whilst bobbing about in the sea.
Transits are the main method of navigation used in international competitions. The top competitors all have books of transits and notes for all the areas and specific holes they have found during scouting.
cheers
dave
www.spearo.co.uk

 

[Murat]

thanks dave, i got what you mean. I know that method but it never worked for me, it seems i always forget the land marks :duh may be you need experiance in this subject. Sometimes its so difficult to find suitable land marks especially when you are far away from the shore, everthing seems so small that even 1 degree of mistake can yield hıundreds of meter wrong result. Of course there are times when i don't even see the land to point a land mark.

Anyway, the GPS i need is one used to pin point the exact location and record it in its memory and helps me to get to the point hasslefree. I never used GPS before so i don't know how they works (except the theory) do you need compass next to GPS to find the recorder memory or GPS handle all the things for you and just show you the way to go with arrow or something smillar?? Really i don't want to end up with something useless for me...

akrikel,

ypu meant direction to go to reach the spot by saying "the arrow in the pic is a go-to-waypoint option which points in direction of travel. only works if unit is actually moving. hope that helps!"
I will tie GPS to float or hold it in my hand in water proof soft case while swimming if thats counts as moving??? :hmm

 

[akrikel]

hey murat. my advice is, if u keen on getting a GPS then go for it! dont worry, you'll get the hang of it in no time. what i meant in previous thread is: GPS calculates position first, then can calculate direction of travel using consecutive positions. this then allows the GPS to tell you wot your direction of travel (course) is and wot it should be to get to your waypoint. if you stand still( or move too slowly or too erratically), the GPS will have trouble calculating a direction of travel and thus you'll see that arrow bouncing around. however, the unit can also tell you a distance and a bearing to the waypoint, irrespective of your speed. so if you know where north is, you can swim towards the waypoint and watch the distance count down. best advice is, keep the antenna area clear, so raise it above your head slighly and keep the unit has vertical as possible. just 1 extra sattelite can vasty improve your accuracy! also, when storing waypoint, take the effort to ensure you getting the best possible position with your unit. at least 6 sats and WAAS enabled if u got it.