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csuhockey3
03-03-2005, 11:14 PM
Hey Folks,

I am taking a course in GPS and was assigned to present something interesting about the subject. Naturally, I thought of the lake. I looked around the forum and found some good information here and there, but I would like to ask you all:

- What GPS units do you use?
- Interesting stories about how GPS was helpful to you
- Advances in GPS/GIS around the lakes region
- What, if anything did you use in the past (more for aircraft)
- Good resources to provide me with more (local) information

Besides discussing how GPS will have a detrimental effect on the sale of props at the local marina, I'm not really sure where I want to go with this. I plan to discuss GPS in aircraft as well, since maritime and aircraft are so closely related. So, to get the creative juices flowing, I turn to you fine people and your infinite wisdom.

Thanks for the help!

BroadHopper
03-04-2005, 12:40 PM
I have a magellan hand held. I only use it on the lake to check my speed. My grandkids uses it to play Geosearch. (www.geosearch.com)
I use it out on the ocean to find Block Island off the coast of RI.
I take it with me when I go hiking in case I get lost, but I find the hiking trails are a bit off on the scale. I heard someone is remapping the trails.
I bring it with me when I do the intercoastal but it is so well mark, I never really had to use it. Guess I'm not much use................... :eek:

Mee-n-Mac
03-04-2005, 01:51 PM
Hey Folks,
I am taking a course in GPS and was assigned to present something interesting about the subject. Naturally, I thought of the lake. I looked around the forum and found some good information here and there, but I would like to ask you all:
- What GPS units do you use?
- Interesting stories about how GPS was helpful to you
- Advances in GPS/GIS around the lakes region
- What, if anything did you use in the past (more for aircraft)
- Good resources to provide me with more (local) information
Besides discussing how GPS will have a detrimental effect on the sale of props at the local marina, I'm not really sure where I want to go with this. I plan to discuss GPS in aircraft as well, since maritime and aircraft are so closely related. So, to get the creative juices flowing, I turn to you fine people and your infinite wisdom.
Thanks for the help!


Like Broadhopper I have a handheld though it's a Garmin. It's not a chartplotter so it doesn't replace my Bizer. I break it out for (some) night trips though I have to say it's more of a backup than a primary device. There's only been 1 time that I was really glad to have had it onboard and that was coming back at night when we ran into fog and rain (see thread on "Most challenging Winni adventure"). Given the improved quality of the newer displays I would probably get a chartplotter if I were to buy one now.

As for presenting something interesting ... hmmm ... not sure how to help you here. I wonder how long it'll be before every can use the "GPS" built into their cell phones for lake navigation? I wonder if GPS units for aircraft usage are different from their terrestrial counterparts in regards to update timing. Consider that it takes time to receive the GPS signals, compute the position and update the display. The display you see is where you was some moments ago. No big deal if moving slowly and the need for precision is low but move fast and need high precision (bass boat and narrow channel :D or plane and runway) and it's a different story. Then again I think we're still some years from GPS only instrument landings (perhaps the pilots out there can comment). I remember talk about a GPS based co-operative collision avoidance system (every plane broadcasts his position to whomever and each plane figures out where it should and shouldn't be) but I don't think it ever got out of the concept stage. Again the pilots here can comment. Someone earlier this year had bought a marine GPS that had a feature where the GPS predicted the boats course some seconds ahead and compared that to known hazards (ie the shore or rocks or ??) and issued a warning if there was going to be a conflict. I thought that was pretty novel for a low cost GPS system.


As for infinite wisdom ...hehehe... I would remind you of what Einstein is quoted as saying about infinite. "Two things are infinite, the universe and ...." well I'll let you look it up. :cool:

upthesaukee
03-04-2005, 10:55 PM
I have a Magellen Map410 GPS with the Lake Winni map from CMap downloaded into it and Bizer's Waypoint file. The map is pretty good, the waypoint file is great and I have added a few waypoints for areas that were not on Bizer's file.

I rely on my Bizer chart and eyes first, and back up my observations with the GPS. At night, the GPS gives me an idea where to look for a marker or island. At anytime, it gives me an accurate measure of speed and heading. If desired, I can set alarms to warn me when I get within a certain distance of any waypoint. Bizer's waypoint file has several "safe passage" waypoints that if you navigate to them, you should remain clear of obstacles (ie, Alton Bay to West Alton...Safe point just east of Sandy Point flasher, just west of Echo Point flasher, east of Little Mark flasher.) When I am in a new or unfamiliar area, it helps to pinpoint just where I am at in relation to markers, flashers, hazards, etc.

In my prior life, I was an air traffic controller, and was always amazed at the RNAV (area navigation) and LORAN navigation equipment. On familiarization rides with some of the airlines, especially when flying late at night, pilots would request a routing from over Ohio, for instance, to the outer fix for Dallas Fort Worth, rather than following the Jet Routes (highways in the sky). Upon approval, the pilot merely entered the coordinates into the equipment, told the equipment to "go to that point" and the autopilot took over. Very interesting to watch the mileage click off from 500 miles out flying at a speed over 500MPH and see the miles clicking off at 8 or 9 or 10 miles every minute!!!! In the cockpit, the obvious advantage for the pilot was fuel savings (shortest distance is a straight line), less distractions (change of frequency for navaids and changing bearings to/from navaids), and happy customers (got them in early).

Personal experience with the GPS...Last July 4th, went to the fireworks at Wolfeboro, and there was no moon, and once past Sewell Point heading to West Alton, there was little visual reference available. There was a pretty good chop from the southwest, so looking over the top of that low windshield could get a little wet. GPS showed me where I was, how I was tracking in reference to my trip over to Wolfeboro (made in daylight and obviously clear of markers and hazards), and where to look for those pesky markers (1 o'clock, 2 o'clock, etc.). Still had to visually pickup Rattlesnake, Ship, Treasure, that pesky black spar off the SE end of Treasure, and Small's Cove Flasher. Did I look at the GPS alot???? You Betcha!!!! Did I just plain navigate off it???? Not on your life!!!!! Did having it on board and up and running make the trip better for me and my passengers????Oh Yeah!!!!!!!!!!!!!

Good luck!!!!

Island Girl
03-05-2005, 07:19 AM
My little garmin will draw a track on a map so I can look at it and tell where I have been before. This allows me to boat at night and in the fog. Several 4am mornings going to shore from the island when there was no visibility, foggy windshield, and rain in my race, the track showed me the way. I know that the map can be inaccurate, but the track is not.

I now bring it with me snowmobiling on the lake to identify islands and where I am.

Geocaching (www.geocaching.com (http://www.geocaching.com)) is a great way to learn to use a GPS. Find hidden treasures anywhere in the world.

I got my money's worth.

Misty Blue
03-05-2005, 05:34 PM
Dear csu:

I am always glad when I hear about boaters not trading in their seamanship skills for a GPS. It's a tool. A great one, but just a tool.

Mine is a Standard Horizon with Bizer C-map of the Lake and Portsmouth-North.

I findit to be the best speed indicator around. It is also the best compass.

I use it annualy to create a deviation chart for my compass. Nutz on.

An other great quality is being able to give a Lat/Long position when you are in trouble. I do many assists both on the Lake and Portsmouth, NH every year and I can't tell you how much time it saves. Give me a position and I am there. No search paterns needed. Great tool.

I'll let you in on a dark secret. Like upthesaukee I was also out on the July 4th 2004. Heading home around 1 AM. I was flying IFR. Man I have a GPS and I'm styling in the dark at 18 knots. My training got the best of me though and I decided to throttle down and act like a seaman. About two minutes later Steam Boat island loomed up before me!

I came to a dead stop, had a bite of humble pie and cruised on home with my tail between my legs.

There is a lesson there.

Good luck with your class!

Misty Blue

JoeP
03-05-2005, 06:08 PM
I also have the Standard Horizon with the C-Map chip of the Lake. Sure makes driving on the lake with the Mrs. much more enjoyable!! Now she can find the markers without continously asking - LOL

ApS
03-06-2005, 07:29 PM
A slow-to-load, but interesting site to chart the GPS satellites' course through the heavens:

http://science.nasa.gov/Realtime/JTrack/3D/JTrack3D.html

Select the GPS (or any other of lots!) satellites from the drop-down menu. Rotate at 100% or 1000%.

csuhockey3
03-08-2005, 08:27 PM
Thank you all for your replies. My presentation went just fine, thanks for your insight. Heads up Misty :eek:

Now it's on to more important things -- like spring break!