CompuServe Messages

GPS Error

    29-Dec-94 06:31:58
Sb: #159698-GPS Error
Fm: Robert Naylor 100144,610
To: Lanny R. Ream 73512,1163
<<Thanks for the info. Wish I could believe your figures, but having spent a field season with a Trimble Scout and occassionally with two other geologists with a Garmin (don't know the model) and a Magellan Meridian I find that the system tends to typically produce readings that vary more like 50-200 m. Such variations can be within an hour or two or several days apart. By this I mean taking a reading and at the same spot taking a reading an hour later or days later and having the two readings differ by that much in lat and/or long.>> Lanny, I think what you are seeing here is more an effect of your use of "budget" receivers, rather than the "design accuracies" built into the control and space segment elements of the system. A Trimble 4000 series receiver or equivalent would not show this level of drift. Not surprised at the level of multipath effects seen in canyons… you'd be better off with more conventional survey tools in those locations. Rob