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ADS-B Receiver

The ADS-B Receiver tile is the diagnostic view of the GDL90 link between your phone and a Stratux or Garmin GTX-345. It's the screen you visit when:

  • You want to confirm the receiver is actually connected
  • You want to see raw frame counts and per-product FIS-B tallies
  • You're troubleshooting why traffic / weather isn't appearing on the radar

For the actual radar display, see Radar scope. For weather text, see FIS-B weather.

What it shows

When you open the receiver tile, you'll see:

  • Connection status: green dot if a frame arrived in the last 3 seconds, red otherwise
  • Sender IP: the IP address that sent the most recent frame (helpful for debugging — should be your Stratux's LAN IP)
  • Total frames: lifetime count since the receiver started
  • Total bytes: lifetime data volume
  • Last frame age: ms since the most recent frame
  • Per-product counts:
  • Ownship reports
  • Traffic reports
  • Heartbeats
  • FIS-B uplinks
  • FIS-B product tallies (when uplinks are arriving):
  • METAR / TAF / PIREP / AIRMET / SIGMET
  • NEXRAD CONUS / NEXRAD Regional
  • Plus a green NEXRAD pill when precip data is flowing
  • Start / Stop button — start the UDP listener, or stop it manually

Auto-start behavior

The receiver auto-starts when you log in (assuming Local Network permission is granted on iOS). You don't normally need to tap Start manually — but if the receiver was stopped (e.g., the app was force-quit), the receiver tile is where you re-start it.

Default port

The receiver listens on UDP port 4000. That's the GDL90 default — both Stratux and GTX-345 broadcast there by default. Custom port? Stop the receiver and start it on a different port via the on-screen control.

Frame rate

A healthy connection looks like:

  • Heartbeat: 1 / second
  • Ownship: 1 / second
  • Traffic: 1 / second per visible target
  • FIS-B uplinks: a steady trickle, varies with weather data freshness

If frames are arriving but counts are wildly off (e.g., 0 ownship despite the Stratux being on), check that the Stratux is actually getting GPS lock (its own status LED).

Troubleshooting

Symptom Likely cause Fix
Red dot, no frames Phone not on Stratux's Wi-Fi network Connect to the Stratux SSID (typically stratux with no password)
Red dot, frames arriving on web Stratux page iOS Local Network permission denied Settings → AZSuite → Local Network → Allow
Green dot but Ownship count stuck at 0 Stratux has no GPS fix yet Wait outside with sky view; Stratux's GPS LED should turn green
Frames arriving but no traffic on radar No traffic in your area, or all traffic is too far/different alt Visit the radar; range may be too tight
FIS-B uplinks=0 despite cruise alt FIS-B coverage requires AGL altitude (typically > 3000 ft AGL) Climb above the FIS-B floor