diff --git a/collector/main.py b/collector/main.py
index 1228eb8..ccc8a45 100644
--- a/collector/main.py
+++ b/collector/main.py
@@ -28,6 +28,21 @@ from maidenhead import latlon_to_subsquare, subsquare_bounds
import re as _re
+def _valid_position(lat, lon) -> bool:
+ """Filter out corrupt or irrelevant positions."""
+ if lat is None or lon is None:
+ return False
+ if lat != lat or lon != lon: # NaN check
+ return False
+ if abs(lat) < 0.01 and abs(lon) < 0.01: # 0,0 = no GPS fix
+ return False
+ if lat < 54 or lat > 72: # outside Scandinavia
+ return False
+ if lon < 4 or lon > 32: # outside Scandinavia
+ return False
+ return True
+
+
def _extract_digis(path: str) -> str:
"""
Reduce a raw APRS path to the actual physical digipeaters that handled it.
@@ -187,6 +202,10 @@ async def ingest_rf(frame: RFFrameIn) -> None:
lat, lon, _ = _parse_position(tnc2)
+ # Nullify invalid positions so they are stored as NULL rather than corrupt data
+ if not _valid_position(lat, lon):
+ lat, lon = None, None
+
logger.info(
"RF %-6s %-9s [%s] lat=%s lon=%s",
"DIRECT" if frame.heard_direct else "VIA",
diff --git a/web/index.html b/web/index.html
index a964cd1..29d002c 100644
--- a/web/index.html
+++ b/web/index.html
@@ -3,7 +3,7 @@
-heardlog ??? APRS RF Coverage
+heardlog – APRS RF Coverage