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CW599 MORSE LAB · CW receiver activity

HF Activity Map

See where receivers are hearing CW — not where transmitters are located.

Loading observations…

Deduplicated reports
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Receivers
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Heard callsigns
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Unlocated reports
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HF Activity Map

Choose AMap if OpenStreetMap cannot load on your network. Both display the same observations.

Band filters describe observed frequencies, not permission to transmit in your location. 160m is included for amateur operating convenience. This version covers CW only.

Help & version history
Reports per receiver grid · fixed scale

Blank areas mean no observations, not closed bands. Receiver density affects counts; a hotspot does not guarantee a contact from your station.

Data: Reverse Beacon Network

Observations by receiver grid

Select a grid to open its details on the map. All counts are also available in this table.

Observations by receiver grid
Receiver gridDeduplicated reportsReceiversHeard callsignsLatest report (UTC)

How this map works

RBN CW reports are deduplicated by receiver, heard callsign, band and UTC minute. Colours show report counts in four-character Maidenhead receiver grids. SNR is not used as a heat score. A reception report is not proof of a completed QSO.

Blank areas mean no observations, not closed bands. Receiver density affects counts; a hotspot does not guarantee a contact from your station.

Map provider

Switch between AMap and OpenStreetMap, using the same AMap configuration as the Maidenhead locator. Chinese pages default to AMap, English pages to OpenStreetMap; a manual choice is remembered in this browser. Changing maps preserves band, time, counts and the approximate view, within each provider’s zoom limits. RBN grids remain WGS-84; AMap display coordinates use the same GCJ-02 conversion as the locator. This does not change aggregation. AMap uses its standard basemap, not a separately licensed advanced world-map service; overseas detail depends on the provider and account. If loading fails, retry or choose the other map; existing observations and the table remain available. Restore defaults clears the map preference as well as resetting filters.

Privacy & requests

No account or location permission is required. Aggregates and Leaflet load from CW599. Selecting AMap loads its JS API and map services; selecting OpenStreetMap requests its tiles. These providers receive normal web request information. Requests already started may finish after a switch. Only the map choice is stored locally; no IP-region lookup is added. This tool does not collect visitor callsigns, locations or audio. Site-wide analytics privacy choices apply separately.

Version history & archive

v1.1.2 (2026-09-22) — Added full Japanese interface, states and current help, with synchronized English/Chinese notes. Data, algorithms and permissions are unchanged. v1.1.1 (2026-09-20) — Added Spanish interface, states and current help, with synchronized English/Chinese notes. Aggregation, data retention and map algorithms are unchanged; no new permissions or collection fields. v1.1.0 — AMap / OpenStreetMap switching, shared locator credentials, remembered choice, local Leaflet assets and retry controls. v1.0.2 — Restored the shared 340px desktop tool selector and its standard styling. Combined the map and right-hand controls in one panel below the observation summary. v1.0.1 — Moved controls to the right and kept help below the table in the content column. v1.0.0 — CW receiver-grid activity, band/time filters, fixed colour scale, accessible table and explicit recovery states. Historical source versions are retained in Git; published releases also have pre-deployment backups. There is no separate public historical app or retained historical RBN dataset.