Skip to content

Received here: passive RX mapping

During an active wardrive, FreqMapper can mark where the connected driving radio heard ordinary Meshtastic traffic on any configured channel it can decode. These Received here markers and purple cells supplement the controlled mapping tests; they do not replace them.

What a purple marker means

A purple RX marker means the connected radio received an eligible text, position, node-info, or telemetry packet on one of its configured channels while the phone had a fresh, accurate GPS fix. The marker is placed at the driving phone/radio's reception location. It does not claim that the sender, a router, or a Watcher was at that location.

  • A hollow marker is waiting for the private sample to be accepted by FreqMapper.
  • A filled marker has been saved.
  • Tap the marker to inspect the driving radio's RSSI/SNR, known hop information, packet type, and optional Watcher comparison.

FreqMapper samples useful receptions instead of drawing every duplicate packet. Mapping-test traffic, self echoes, MQTT-path reports, stale or inaccurate GPS, and packets without plausible radio metadata are excluded.

Purple coverage cells

Purple cells summarize what the driving radio heard in that area. Their light-to-dark quality is calculated from that radio's receive RSSI/SNR, not from a Watcher's signal and not from a sender's advertised position:

  • Dark purple: strong RX.
  • Purple: fair RX.
  • Light purple: weak RX.

The public map and mobile maps show TX and RX evidence together. Display priority is:

  1. Positive verified TX coverage, including an amber degraded state, remains visible over passive RX.
  2. Purple RX can fill an untested, pending, or red/not-heard area.
  3. A later positive verified TX test replaces purple.

This is display priority only. FreqMapper preserves the underlying TX and RX records separately, and purple RX never creates verified coverage. The public leaderboard awards a separate RX point once per mapper and distinct 300 m receive area; repeated packets in that area add samples but not points. Approved partner applications can read explicitly typed passive RX events through the combined or RX-only partner contract; an RX event is never labelled as third-party verified TX.

The public map combines accepted samples into 100 m detail or 300 m overview cells. It publishes the cell quality, sample count, and number of contributing mappers—not individual markers, sender or packet IDs, trip or installation IDs, timestamps, exact sample positions, or Watcher-comparison details.

See the complete map legend for every TX/RX cell, session marker, and non-color outline cue.

Watcher comparison

After the driving radio reports a reception, FreqMapper can compare its sender and packet ID with reports from distinct approved Watchers. The marker can show up to three Watcher details and separately identify a Watcher assigned to another active region.

A match confirms that both the driving radio and that Watcher reported the same packet near the same time. It can help describe how widely the packet was observed, but it does not prove the exact route, the driver's distance from a Watcher, or that every copy followed the same hops. Zero Watcher matches still means the driving radio received the packet; it is simply uncorroborated RX.

Background behavior

An active wardrive's GPS recording, BLE radio capture, scheduled mapping tests, and private RX sampling continue when you open another FreqMapper tab or temporarily use another app, subject to Android and iOS background-execution rules. Offscreen map/result downloads may pause to save battery and network. When you return, the app refreshes the display from the running session and queued uploads.

Force-quitting the app or operating-system termination is not guaranteed to preserve active background execution. Keep the required Bluetooth and location permissions enabled, and reconnect the radio if the operating system ends its connection.

Coverage degradation

Verified coverage never expires merely because nobody revisited the area. Its last-known color remains until new credible testing provides contrary evidence.

  • One credible completed miss after a verified result keeps the last-known coverage color.
  • Two credible misses from at least two separate wardrives change the cell to amber degraded.
  • Three credible misses change it to red not heard.
  • A new verified Watcher receipt restores the measured coverage color immediately.

A miss is credible only when the normal 90-second matching window completed and an approved Watcher in that region was independently active around the test. Pending tests, passive RX, and tests made without an active eligible Watcher do not degrade coverage. Repeated attempts are collapsed into ten-minute buckets so one burst cannot rewrite the map.

Last updated: 2026-09-07