From the Forums Friday 2008-05-30
Another episode of From the Forums Friday is here, this time the educational (FAQ type) edition. Lots of people asked this week “Is memory card required” for a GPS. In the majority of cases, NO! Shame on those retailers that try to convince users otherwise and try to sell them SD cards at prices ten times over market value! We’ve previously discussed this in our article Do I Need an SD Card for my GPS?
Why does my GPS create Different routes between same two points? There are quite a few reasons why, and I discuss a few of those reasons in that forum thread. Things just are not always the same going backwards.
The GPS system is fairly accurate horizontally, not as much so in the vertical axis until WAAS is applied. But in most car navigation systems the elevation isn’t really an important value to have nailed down. Still you might like to know why the “Where Am I” elevation keeps changing.
Quite a few users this week were having issues with their GPS drawing their position slightly offset from where they thought they were or where they actually were. This lead to questions about “accuracy”. People tend to think that since GPS has an accuracy of about 10 meters that the road database is also that accurate, and that street number address locations are that accurate. Unfortunately that is not the case. But we talk briefly about how to measure GPS accuracy when it comes to the coordinates themselves.
With summer vacations lining up, more and more people want to create their own route from their computer and transfer it to their GPS. Depending on the model– TomTom, Garmin, and HP have some options for doing that, each with their own advantages and disadvantages. For example the TomTom method is the only one that is Mac compatible, but doesn’t run in full-screen. Garmin doesn’t include the necessary software in the box, and HP’s solution is a little cumbersome. People also discuss some third party systems available for TomTom devices to plan routes from a computer as well.
Many of the new Garmin devices have a nifty feature for finding where you parked. While the convenience of having a function designed specifically for that task is a good thing, you can make it work on other devices such as TomTom models as well. None will help you that much if you are in a parking garage where you don’t have a GPS signal, but they all will come in handy from time to time.