Re: app for precision coordinates

Andy Burns <usenet@andyburns.uk> wrote:

VanguardLH wrote:
 

Don't remember seeing a smart
phone stating it can use DGPS, so you'll likely have to find a GPS
receiver that can find DGPS stations.

 
Build your own RTK GPS
<https://www.youtube.com/watch?v=Oc1LBFDj2MA>
 
(yes, I know the O/P wants to spend on trees, not tech toys).

The video author mention RTK (Real-Time Kinematic) positioning which
sounds very much like DGPS (Differential GPS) where land-based stations
knowing their exact position relay that to the roving GPS receiver to
add to the positioning it gets from the satellites.

The author said the range of the RTK land station is 20 km (12 miles).
I thought it was 200 miles for DPGS, but then that couldn't get around
the Earth's curvature.