Tech Tips


Important: Users of R-DAS Tiny, hardware Version V4.2

As of V4.2 the R-DAS uses a different pressure transducer. Users of R-DAS Tiny with this hardware version will need to set the proper calibration values in the user interface to guarantee parachute deployment at the correct altitude. To do this:

  1. Connect the R-DAS to the PC
  2. Go to the 'calibration values' menu, and  press the 'GET' button. This will import the calibration values from the R-DAS unit.
  3. Press 'Set as default'. This will make the current calibration values the default values for the GUI.
  4. After the new calibration values are set, the barometric value will be set correctly. Note that the altitude beep-out is incorrect with the current version of the firmware. Version V4.2 of the firmware (to be released soon) will solve this issue.
Windows Vista Hints:  Associate .rd files with the R-DAS GUI

The R-DAS GUI program registers the .rd file type when it is started. It does this by writing to the appropriate keys in the system registry. On Windows Vista, access to these registry keys is limited to processes that run with administrative privileges. The result is that the R-DAS GUI is unable to register its file type.

Solution: Run the R-DAS GUI once as administrator.
right click the R-DAS application in the start menu, and select "Run as administrator". The R-DAS GUI will now register its file type. You can close the application after it has started. The .rd file extension is now registered to the rdas.exe executable. You have to run the R-DAS GUIi as administrator only once. After the file type has been registered you can run the R-DAS GUI as normal user as usual, e.g. by selecting it from the start menu, or double-clicking on an .rd file.

R-DAS transmitter protocol:

Description of the R-DAS transmitter protocol. This information is useful for debugging telemetry systems as well as hooking up long-range telemetry systems. Click here to read the protocol description.

The 'i' command:

The 'i' command can be used to show the status of all inputs of the R-DAS. Measurements are repeated until the 'return' key is hit. Use the terminal built in the R-DAS user interface to view the results. Click here to read the command description.

GPS V2.0 (38 mm GPS):

Manual annex for 38 mm GPS. Click here to read this manual.

How to connect multiple expansion boards to one R-DAS:

If you want to connect multiple expansion boards to one R-DAS, just crimp multiple connectors on a single ribbon cable. Make sure all pin-1's (little triangle on the connector) are attached to the same wire. The total length of the ribbon cable can be up to 1 meter (about 3 ft). If you need ribbon cable or connectors, see our ordering page.

How to configure Google Earth for 3D GPS view:

By default Google Earth clamps all altitudes to ground level. To get a nice 3d graph do the following:
First export .gpx file from R-DAS GUI.
Load it through file-open (select gps file type). 
Tilt the image down.
Go the the "Temporary Places" in the "Places" overview. 
Right-click on 'waypoints' and select edit - advanced - location, and select "absolute" for the altitude i.s.o. "clamp to ground track" 
Repeat the last step for the 'tracks', and also select "Draw lines with skirts".

A typical example is shown in the figure below (click to enlarge).