Receiver Configuration File

All the necessary configuration of your receiver is kept in one configuration file, which you pass as an argument at the program's start-up.

RF Section

Calibrate the frequency

For more information take a look at the ogn-rf install Readme

RF:
{
    # [ppm] frequency correction applied to the Rx chip ("big" R820T sticks have 40-80ppm correction factors, measure it with gsm_scan)
    FreqCorr = +15;

    # for frequency calibration based on GSM signals
    GSM:                     
    {
        # [MHz] should be selected to cover at least one broadcast channel in the area (find the best GSM frequency with gsm_scan) 
        CenterFreq  = 952.8;

        # [0.1dB] Rx input gain for GSM frequency calibration (beware that GSM signals are very strong !)
        Gain        =  40.0;   # [dB]  RF input gain (beware that GSM signals are very strong !)
    } ;
    ...
} ;

Activate the power supply for preamps

Please visit the related subsection of the manual installation guide before activating the bias-T.

RF:
{ 
    ...
    # activate the power supply for preamps (only: RTL-SDR.com v3 dongle)
    BiasTee      = 1;
    ...
    OGN:
    {
        # [0.1dB] Rx input gain for OGN reception, valid gain settings are : 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6
        Gain = 22.9;
    };
    ...
};

Use multiple rtlsdr devices

If you want to set up multiple receivers on a RaspberryPi, please visit the multiple receiver wiki

In your ogn conf file you can set the receiver/dongle to use (untested, according to mailing list 2014-06-18):

RF:
{
  ...
  Device   =   0;          # [index]    0 = 1st RTL2832 USB stick, 1 = 2nd USB stick, etc.
  ...
};

Position Section

Setting the correct GPS location

In your receiver's configuration file you need to set the GPS location and elevation of your antenna correctly:

A simple way to find the correct values: Online geoid calc

Alternatively, go to: https://www.freemaptools.com/elevation-finder.htm

Place the marker where your receiver will be.

It will give you data like this:

    Latitude - Longitude:
    51.496645,-0.176341

    Lat: 51° 29' 47.922"
    Long: -0° 10' 34.8276"

Copy the second line:

    51.496645,-0.176341

And add 0s at the end to get 7 decimal places:

    51.4966450,-0.1763410

Set the latitude and longitude and altitude in your configuration file and save it:

Position:
{ 
    # [deg] Antenna coordinates (with 7 decimal places)
    Latitude   =   +51.4966450;
    Longitude  =    -0.1763410;

    # [m]   Altitude above sea level incl. antenna height
    Altitude   =  19;
    ...
};

APRS Section

Insert your call sign

Select the callsign for your receiver with a maximum of 9 characters. Please apply the naming conventions.

Note: After selecting your call sign don't forget to add your receiver to the list of receivers.

APRS:
{
    # APRS callsign (max. 9 characters). Please apply the naming conventions: http://ognproject.wikidot.com/receiver-naming-convention
    Call = London;
    ...
};

Use your own aprs server

If your aprs server listens on localhost at port 14580, you can use this configuration.
Note: You have to forward the packets yourself to the ogn network!

APRS:
{
     ...
     Server = "localhost:14580";
     ...
};

DDB Section

Enforce strict opt-in (since v0.2.4)

Add the following section.

DDB:
{
    ...
    UseAsWhitelist = 1;
    ...
};

Configuration file template

The following template contains some optional arguments for special setups. Use "#" to comment out optional arguments you don't need.

RF:
{ 
    # [ppm] frequency correction applied to the Rx chip ("big" R820T sticks have 40-80ppm correction factors, measure it with gsm_scan)
    FreqCorr = {{ + or - ogn_freq_corr }};

    # optional: activate the power supply for preamps (only: RTL-SDR.com v3 dongle)
    # BiasTee =  {{ ogn_bias_tee }};

    # optional: rtl-sdr device index
    # Device = {{ ogn_device_id }};

    # optional: char[12] serial number of the rtl-sdr device to be selected
    # DeviceSerial = {{ ogn_device_serial }};

    # optional: name of the fifo-pipe, relevant for multiple receivers: http://ognproject.wikidot.com/multiple-receivers-configuration-on-raspi
    # PipeName =  {{ ogn_rf_fifo_name }};

    OGN:
    {
        # [0.1dB] Rx input gain for OGN reception, valid gain settings are : 0.0 0.9 1.4 2.7 3.7 7.7 8.7 12.5 14.4 15.7 16.6 19.7 20.7 22.9 25.4 28.0 29.7 32.8 33.8 36.4 37.2 38.6 40.2 42.1 43.4 43.9 44.5 48.0 49.6
        Gain = {{ ogn_ogn_freq }};
    };

    # for frequency calibration based on GSM signals
    GSM:
    {
        # [MHz] should be selected to cover at least one broadcast channel in the area (find the best GSM frequency with gsm_scan)
        CenterFreq  = {{ ogn_gsm_freq }};

        # [0.1dB] Rx input gain for GSM frequency calibration (beware that GSM signals are very strong !)
        Gain        = {{ ogn_gsm_gain }};
    };
};

Position:
{
    # [deg] Antenna coordinates
    Latitude   =   {{ ogn_pos_lat }};
    Longitude  =   {{ ogn_pos_lon }};

    # [m]   Altitude above sea level incl. antenna height
    Altitude   =   {{ ogn_pos_alt }};

};

APRS:
{
    # APRS callsign (max. 9 characters)
    Call = {{ ogn_aprs_callsign }};

    # optional: APRS server host:port
    # Server = {{ ogn_aprs_server }};
};

DDB:
{
    # optional: Enforce strict opt in
    # UseAsWhitelist = {{ ogn_ddb_useaswhitelist }};
};

HTTP:
{
    # optional: change the http diagnostics/debug port for multiple receivers
    # Port=8080;
};
Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License