TeleGPS Application
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The rest of the dialog contains the parameters to be configured.
3.13.1. Frequency
This configures which of the frequencies to use for both telemetry and packet command mode. Note
that if you set this value via packet command mode, the TeleDongle frequency will also be automatically
reconfigured to match so that communication will continue afterwards.
3.13.2. RF Calibration
The radios in every Altus Metrum device are calibrated at the factory to ensure that they transmit and
receive on the specified frequency. If you need to you can adjust the calibration by changing this value.
Do not do this without understanding what the value means, read the appendix on calibration and/or
the source code for more information. To change a TeleDongle’s calibration, you must reprogram the
unit completely.
3.13.3. Telemetry/RDF/APRS Enable
Enables the radio for transmission during flight. When disabled, the radio will not transmit anything
during flight at all.
3.13.4. Telemetry baud rate
This sets the modulation bit rate for data transmission for both telemetry and packet link mode. Lower
bit rates will increase range while reducing the amount of data that can be sent and increasing battery
consumption. All telemetry is done using a rate 1/2 constraint 4 convolution code, so the actual data
transmission rate is 1/2 of the modulation bit rate specified here.
3.13.5. APRS Interval
How often to transmit GPS information via APRS (in seconds). When set to zero, APRS transmission is
disabled. Note that a single APRS packet takes nearly a full second to transmit, so enabling this option
will prevent sending any other telemetry during that time.
3.13.6. APRS SSID
Which SSID to report in APRS packets. By default, this is set to the last digit of the serial number, but can
be configured to any value from 0 to 9.
3.13.7. APRS Format
Whether to send APRS data in Compressed or Uncompressed format. Compressed format is smaller
and more precise. Uncompressed format is older, but may work better with your device. The Kenwood
TH-D72 only displays altitude information with Uncompressed format, while the Yaesu FT1D only
displays altitude with Compressed format. Test before you fly to see which to use.
3.13.8. Callsign
This sets the call sign included in each telemetry packet. Set this as needed to conform to your local
radio regulations.
