Graph Question

[crappiechappy]

I'm thinking of buying one of the newer sonars with a gps combo units, but I'm not sure how the speed is calculated? Is it by the gps or by the wheel on the speed probe? I am trolling at such slow speeds that the wheel on the speed probe will not register unless you make some homemade modifications to the wheel. I want to be able to use the gps for my speed readings and still have a full view of the sonar screen while I'm reading it. I'm sure someone can provide me with some input on this before I go out and spend a bunch of money. As always, thanks in advance for any help!!

[Shellback]

Good question and I can't answer it. I do have a Humminbird Matrix 37 with the speed wheel, and also a Garmin GPS. Neither is much good under 1 MPH, and some of the differences between a paddle wheel and GPS can be caused by currents. The paddle wheel gives you your speed over water, and the GPS your speed over land. If you were fishing a river with a 2 MPH current and heading upstream at 1 MPH, your paddle wheel would indicate 3 MPH and your GPS would indicate 1 MPH. In reality, for fishing, the paddle wheel speed would be the most important to you as far as bait or lure action.

[PieEye]

On most GPS units there is a digital display that will indicate speed. It measures in .10 of MPH. Very accurate. I Use the Lowrance LMS 480. It has split screen GPS/Sonar/Flasher. You can retrace a trail at the exact same speed. Most times I get caught watching the screen for all the cool stuff and forget to watch the poles... LOL The hotmaps are pretty good but may be a touch outdated. I know they saved me as I was caught on Grenada in high winds. I put in at Torrance and headed for the Yellow and Gums Crossing. When I came back... The ole GPS took me right back to the spot where I put in even tho the shoreline looked all alike.


PieEye

[Team Crappie]

Crappychappy, the newer sonar/gps combo units usually come with a gps antenna which accurately measures your speed. No more wheelin' it. I took my boat out of the water last fall and found a little fishing line wrapped around it. No doubt my speed reading was off. The units from Lowrance like the LMS-332c,337c, and the brand new 334c are great with many features to help fishermen. One of my favorites is the Hotspot cards you can plug into your fishfinder for your area which will show you great details including lake contours and river channels. The gps will help guide you right to the ledges, drop offs, points, etc. You can scout out lakes and know where you want to fish before you even get there!

[frank lawhead]

I HAVE A GARMIN 76S THAT READS SPEEDS DOWN TO .4 OR .5 REAL GOOD FOR SPIDER RIGGING

[L.A. stumpjumper]

I have a Hummingbird Matrix 27 with GPS antenna and it displays GPS speed on the graph display. Any speed under 10 mph it displays in tenths, over 10mph it displays in whole numbers.

[Big George]

gps doesnt lie I pull jigs by using the gps all the time

[jhef]

i have the garmin 176 combo, speed works off of gps.it also has the map plug in available as well..

[guest01]

with my matrix 17 with gps it works the speed by the gps. i can go into the menu and tell it to show me my speed while still in full sonar mode. i can even tell it where to diplay the speed and temp like upper corner or lower corner

[FisherMike]

LMS332C for me.

Last unit I'll ever buy.