Accuracy?
Author
Discussion

covboy

Original Poster:

2,593 posts

197 months

Tuesday 25th May 2010
quotequote all
How accurate are current GPS systems. Borrowed a friend GPS over the weekend (not a satnav- a dedicated speed device) and was surprised at the difference in indicated speeds. I know speedo’s are supposed to read higher, but indicated 70mph on the speedo showed about 65/66 mph on the GPS and indicated 70mph on the GPS was nearer 77mph on the speedo .?
Just seemed a big difference

Dave^

7,789 posts

276 months

Tuesday 25th May 2010
quotequote all
Sounds about right...

GPS should be pretty much bob on, on a flat, level, straight road...

The GPS speed is a little laggy too... it might take a second or two to settle down to the correct, accurate speed...

IE - nail your car upto 30mph, and you're likely to be doing over 30 by the time the GPS speedo read 30... If that makes sense...