Payload Examples

The best way to understand the payload format is to read actual transmissions. This page shows the range, from the minimal to the complete.

The format in one line

SOS DE <IDENTITY> <LATITUDE> <LONGITUDE>

Full details and the field-by-field rules are on Config Payload Format.

Example 1: the minimal emergency

With identity and GPS disabled:

SOS

Three characters, seconds of airtime, unmistakable. This is the fallback when nothing else is configured (see GPS Failure Contingency).

Example 2: identity added

SOS DE IK2XYZ

The distress signal plus the callsign: the receiving side now knows WHO. This is the Callsign Identification requirement in its minimal form.

Example 3: the full payload

SOS DE IK2XYZ 45.8325 6.8650

Identity plus position: the complete report. The coordinates are in decimal degrees, 5 decimals (see GPS Coordinate Systems).

Example 4: the name variant

For the unlicensed builder, the identity can be a name:

SOS DE MARIO ROSSI 45.8325 6.8650

Only capital letters A-Z and digits transmit (see Config Payload Format), so names are converted to uppercase.

The airtime math

At 12 WPM, the full payload is roughly 30 - 35 seconds of key-down time (see Firmware TX Scheduler for the timing consequences). Keeping the identity short is a battery and duty-cycle decision, not just a style one.

Related pages

• Config Payload Format for the rules
• Morse Letter Table for the codes
• Mode Beacon for the mode