Cheap GPS unit with ~3 ft or better accuracy, used or otherwise.

[Nate]

All,

I'm wanting to mark out some points on my property based on lat/lon, and need a GPS unit I can carry around that will give me a ~3 ft or better accuracy under some tree cover (lot has a decent amount of trees.) I can carry my laptop or phone to run software that will do post-processing. Ideally something $300 or less (used is fine.)

Just need to know recommendations for a complete solution (I saw a lot of items on ebay for Trimble and others, but, don't know if they have all of the parts I need, etc.)

Thanks!

Nate

 

[Nuvi-Nebie]

I think it may be difficult to find what you are looking for at that price, the 'standard' GPS can't guarantee 3 feet accuracy and anything above that using multiple satellite bands, external radio beacons, RTK etc. are usually thousands of dollars. As far as I am aware, post processing is only carried out on these 'surveying' units such as Trimble etc. as the data required is not available from standard units

The standard units can improve accuracy by carrying out 'GPS averaging', where a unit is kept stationary for an extented period with lots of measurements taken and then averaged, to get a better guess at the location

 

[albert]

All,

I'm wanting to mark out some points on my property based on lat/lon, and need a GPS unit I can carry around that will give me a ~3 ft or better accuracy under some tree cover (lot has a decent amount of trees.) I can carry my laptop or phone to run software that will do post-processing. Ideally something $300 or less (used is fine.)

Just need to know recommendations for a complete solution (I saw a lot of items on ebay for Trimble and others, but, don't know if they have all of the parts I need, etc.)

Thanks!

Nate

Commercial and military gps perhaps but not consumer / civilian gps. Military I remember reading years back is into mm accuracy for different types of gps controlled equipment.
_____

The United States government currently claims 4 meter RMS (7.8 meter 95% Confidence Interval) horizontal accuracy for civilian (SPS) GPS. Vertical accuracy is worse. Mind you, that's the minimum. Some devices/locations reliably (95% of the time or better) can get 3 meter accuracy.Dec 10, 2012

See Document "GLOBAL POSITIONING SYSTEM STANDARD POSITIONING SERVICE PERFORMANCE STANDARD"

http://www.gps.gov/technical/ps/2008-SPS-performance-standard.pdf

General GPS accuracy information: http://www.gps.gov/systems/gps/performance/accuracy/

I've read with some consumer/civilian gps units are able to achieve around ~2 meter accuracy without some form of correction technology.