Beacons

Position reports, objects, trackers, and custom beacons

Beacons are periodic APRS transmissions that announce your station’s position, capabilities, or other information. Graywolf supports multiple beacon types, each with independent scheduling and channel assignment.

Beacons page showing a position beacon with GPS, SmartBeacon settings, and turn-based beaconing
A position beacon with live GPS, SmartBeacon rate adaptation, and turn-based corner pegging

Beacon Types

TypeDescription
position Standard position report with symbol and optional comment. The most common beacon type for fixed stations.
object Named APRS object (repeater, event, landmark). Appears on maps with its own callsign-like identifier.
tracker GPS-driven position beacon with SmartBeacon rate adaptation. For mobile stations.
custom Raw APRS info field. Full control over the transmitted packet content.
igate iGate status beacon. Automatically includes iGate statistics in the comment.

Common Settings

FieldDefaultDescription
channel Radio channel to transmit on
callsign Source callsign (e.g., N0CALL-5)
destination APGRWF Destination address (identifies software)
path WIDE1-1 Digipeater path
every_seconds 1800 Beacon interval (30 minutes)
delay_seconds 0 Initial delay before first beacon
slot_seconds -1 Fixed slot (seconds past the hour, −1 = unset)

Position

Position beacons can use a fixed latitude/longitude or pull live coordinates from a GPS receiver:

FieldDefaultDescription
use_gps false Use live GPS position instead of fixed coordinates
latitude Fixed latitude (decimal degrees, north positive)
longitude Fixed longitude (decimal degrees, east positive)
alt_ft 0 Altitude in feet
ambiguity 0 Position ambiguity (0–3, per APRS101 ch. 6)
compress true Use 13-byte base-91 compressed position format
messaging false Indicate message capability (= vs ! prefix)

Symbols

APRS symbols are selected with a table and symbol code character:

FieldDefaultDescription
symbol_table / Symbol table: / (primary) or \ (alternate)
symbol Symbol code (single character, e.g., - for house)
overlay Overlay character for alternate table symbols

Comments

Beacons can include a static comment or dynamically generate one by running a shell command:

comment Static comment text appended to the position report
comment_cmd Shell command whose stdout becomes the comment (e.g., weather data)

PHG and Repeater Info

Power-Height-Gain-Directivity (PHG) fields describe your station’s RF capabilities per APRS101 chapter 7:

powerTransmitter power in watts
heightAntenna height above average terrain (feet)
gainAntenna gain in dB
dirAntenna directivity (0 = omni)
freqOperating frequency (MHz)
toneCTCSS tone (Hz)
freq_offsetRepeater offset (MHz)

SmartBeacon

SmartBeacon adapts the beacon rate based on speed — faster movement means more frequent beacons, standing still means fewer. Enable it on tracker type beacons:

SmartBeacon Parameters
FieldDefaultDescription
smart_beacon false Enable SmartBeacon rate adaptation
sb_fast_speed 60 Speed (km/h) at which fast rate applies
sb_fast_rate 60 Beacon interval (seconds) at fast speed
sb_slow_speed 5 Speed (km/h) at which slow rate applies
sb_slow_rate 1800 Beacon interval (seconds) when slow/stopped
sb_turn_angle 30 Turn angle threshold (degrees) for corner pegging
sb_turn_slope 255 Sensitivity factor for turn detection
sb_min_turn_time 5 Minimum seconds between turn-triggered beacons

SmartBeacon requires a GPS source. Configure one on the GPS page and set use_gps: true on the beacon.

Immediate Send

Any beacon can be triggered immediately via the API, bypassing the normal schedule. Use POST /api/beacons/{id}/send or the Send Now button in the web UI.

API Reference

MethodEndpointDescription
GET/api/beaconsList all beacons
GET/api/beacons/{id}Get a single beacon
POST/api/beaconsCreate a new beacon
PUT/api/beacons/{id}Update a beacon
DELETE/api/beacons/{id}Delete a beacon
POST/api/beacons/{id}/sendTrigger immediate transmission