Originally Posted by Diesel Benz
I don't understand these "middle of the lake" errors, perhaps your terrain is a lot more difficult than that I'm driving but even my small BT GPS device that I use with a cell phone has never done that really. Are we talking about old GPS implementations, not SIRF III or similar?
My car GPS is always immediately ready even if I start driving from an underground parking lot. My BT GPS takes ages to get a fix if I start from no satellite visibility and keep on driving in a city area without waiting stationary for a fix first.
The "middle of the lake" errors are accumulation of errors the MB system makes.
You think the system is immediately ready, when in fact the system is lying to you saying about GPS, when in fact you are driving on compass and odometer, till the system catches up satellite signals. I see it all the time, that after starting on the street the MB software is showing me driving on the street parallel to the one I am on. After a minute when it finally logs into satellites my position "jumps" a block. Bad come to worse, I prefer to have message about no signal, than misleading (fake) position.
In my wagon I have HD stand for the laptop and have no problem seeing it in CA sunlight. On the top of good quality screen, the laptop software gives me voice command (with 8 voices to choose from) so observing the screen during driving is not necessary. Our 2001 MB GPS does not have voice command, so I wonder if newer does. The laptop software is also having Topo version, what gives you 3-dimensional view. It is usefull for night, especially heavy rig driving, when you can speed up "seeing" grades up front. While not during the driving, you can "fly" over the area and see what is on the other side of the mountain. With internet connection youo can download actuall aerial pictures to the view. Very impressive when you watch Mt Hellen during activity.
Than we have to understand, that software can't be better than our government mapping. In my county we have some roads, that show about 1/8 mile south to the actual position. Driving there, my route is going parallel showing driving over the woods. Than each software has been updated some time ago. My Street Atlas 2005 has "no knowledge" about freeway 210 east of Glendora that was finished in 2000. Each time I drive there, have to turn the voice command off, because that (otherwise nice) voice keeps telling me to turn around from the swamps.
On the top of the GPS issues - around military bases the signals are scrambled.