Lowrance Baja 540c not mapping correctly

[jjstahl3]

I have a new to me 540c and everything seems to be working fine except it seems to be showing my position off by a fair amount - I have tried to find someone with a similar problem but I cant see any threads with this happening - I read to keep the puck 3 feet away from the unit - but what am I missing? Is there a way to calibrate these or something else going on?

[FishPOET]

Welcome to the nightmare that is Lowrance. My antenna is mounted on the roof. I don't use mine for on highway stuff at all. I typically don't zoom closer than 1-1/2 miles. Sometimes my tracks are off trails like you have in the picture.

[jjstahl3]

that's a huge disappointment - my little garmin doesn't do this but the screen is tiny so I was hoping that the lowrance would be a better in car unit

[YukonRob]

Yup, I very often find myself driving in the ocean, at least according to my Lowrance.

[adventureduo]

My 840c does the same thing. I tend to not use it for street as well, but seen it like that on trails before.

[Key-Lock]

You might want to go into the Setup menu and see what datum the unit is set on. When I worked in the field we we're always changing the unit datum to match our paper maps. The unit datum should match the background map datum, which I'm guessing is WGS 84.

[RobRed]

I hope I'm not being too much of a dick but why do you guys put up with that? I dumped my my dedicated units about 2 years ago for an iPad 3G and haven't looked back. I got tired of fiddling with what didn't work. I know you have a big investment in these units but shouldn't it just work?

[jjstahl3]

I don't think so I have a iPhone but usually lose service right when I need it so I thought this would be a good in car solution I assumed it would be dead on the maps but I guess it has a little variation

Still will give a piece I mind on where we are when we lose service - I'm going to try a few other map sets and see if I get the same results

[RobRed]

I don't think so I have a iPhone but usually lose service right when I need it so I thought this would be a good in car solution I assumed it would be dead on the maps but I guess it has a little variation

Still will give a piece I mind on where we are when we lose service - I'm going to try a few other map sets and see if I get the same results

This is a common misunderstanding about what and how an iOS device (iPad) works for GPS. GPS functionality does not rely on "service". Take a look at this if you're interested in the topic http://forum.tlcfaq.com/viewtopic.php?f=6&t=26

Back to your Lowrance issue... it seems to me that these systems are more like a pure chart plotter meaning you are getting raw GPS data including the errors. Most modern on road nav units like a Garmin or say a Pioneer in-dash unit have software that corrects for these errors and will plot you on a road because it figures that the road you are paralleling is the right path. Some systems like the Pioneer (or iPad 2/iPhone4) have 3d gyros and accelerometers to further calculate the error rate down. Those additional sensors also enhance the off road error rate by determining "drift" and correcting. None of these solutions is perfect but one of the big reasons I jumped to the iPad was the software and mapping gets near continuous updates if there is an issue or new feature to be added. I'm not trying to talk you out of the 540 but there are alternatives.

[spressomon]

Yep...my 540C does it although sporadically/inconsistently. I thought it might have been signal interference from the Spot II that sits next to it...but it does it whether or not the Spot II is on/off.

RR: For off-road nav'ing the Lowrance Baja is still, overall, a better unit for my needs and application than anything on the iPad. Pick your poison. Its something we agree to disagree on


I hope Craig and his future Overland Navigator app will give me reason to try my iPad, again, for off-road nav'ing. There is nothing more I'd like, GPS related of course , than to be able to divorce myself from Lowrance. But for now its the lesser of the available evils (again...for my needs and application). YMMV...and apparently does