These are notes transcribed from training received 5/13/2009

GPS General Information

The GPS uses the US and Russion satellites (Glomass satellites). Once the base is set on a known point. The rover is accurate to +- 1cm horizontal, +-2cm vertical with a 2 mile range.

You can set the point using http://www.ngs.noaa.gov click on opus. It takes two hours to have the GPS gather data for a fixed point. You need to do this right away! When you document how to do this, put it on it's own page.

Data collector state

• Autonomous – NOT GOOD, means not connected.
• Float – Signal is there, but not real time or not in phase. Wait, it should correct itself
• Fixed – You're good

When you start up the system you should check PDOP (Pseudo Dilution of Precision) PDOP is related to satellite geometry. Close together → PDOP increases. Under 6 is good.

To access help go to http://Hayeshelp.com, User=trial, pass=topcon

N/E/E → Northerning, Easting, Elevation

Tennessee 4100 Network is apparently our local grid.

Projection types

State Plane

• WSG84 Lat/Long (Tennessee) (No Tran)
• NAVD88
• Localization
• One Point Setup

Localization

You can localize your measurements to grid oriented to true north using a One Point Localization or you can localize your measurements to an arbitrary grid system oriented whichever way it is oriented using a Multi-Point Localization.

One Point Localization

To setup One Point Localization assumes that you are orienting using true north and that any existing grid is oriented in that direction.

1. Create a point (point 1) at 10000, 10000.
2. Setup the base on point 1. Measure that point and call it base point 1.
   1. At this point you may optionally measure several other points as well.
3. In the menu, click on Setup GPS, Localization, (there should be nothing so...) Click Add
4. Select Point 1 for your Local Point, and Base point 1 for your WGS84 Point.
5. Click OK.

Multi Point Localization

If you have used an assumed north or some other value, then you need to do a multi-point localization. This is when you take several points and tack your local points to geodetic. Three is the bare minimum, and 4 is really necessary. This is precisely what we will need to do in Israel to get the GPS receiver into the local grid system that we used last year.

1. Connect to the base reciever.
2. Click Setup Survey, Start Base.
3. The base is setup on a new point (a point that does not exist)
4. Click Auto Position to get several measurement, then click stop
5. Click Start Base
6. Connect to the Rover
7. Survey, Topo - Check to see that we are Fixed (green) and that we are talking to the base. Then exit out
8. Click Setup GPS, Localization
9. Assuming there is nothing there. Click Add Choose your first point in the existing grid system for both the Local Point and the WGS84 Point. Physically go there and place the rover on the point (preferably in a bi-pod) and click measure. The remote will tell me that this point already exists. Do not rename it, instead click "Store As Check Point". This matches the GPS reading to the existing point in the local grid. Click OK, then Click OK AGAIN (out of the Add Point screen).
10. Repeat this process for each of the remaining 3 points in the local grid system