Kalundborg Transmitter
Kalundborg Transmitter was a major Danish radio facility at the harbor of Kalundborg on the island of Zealand. It handled long‑wave and medium‑wave broadcasts for many years.
What it did
- Longwave service on 243 kHz began on 27 August 1927 with 300 kW. It ended on 31 December 2023.
- Medium‑wave service on 1062 kHz began on 1 October 1951 with 250 kW and ended in June 2011.
Key changes over the years
- 15 February 2007: Longwave transmissions were suspended after 80 years.
- 3 October 2008: Longwave resumed in DRM mode at a reduced power of 200 W after aerial upgrades.
- 16–31 October 2009: The old reserve transmitter was used temporarily for both MW and LW.
- Mid‑2011: The medium‑wave transmitter was taken out of service; a new 50 kW longwave transmitter replaced the MW service.
- 6–12 September 2012: The station also broadcast BBC programmes in DRM mode for a broadcast exhibition in Amsterdam.
End of service
- 1 November 2023: Shipping forecast bulletins stopped.
- 31 December 2023: The longwave service closed completely.
Reception and coverage
- The longwave signal could be received outdoors at about 800–1,000 km with a standard radio, and up to about 1,500 km with a better antenna.
Memorial broadcast
- Every year on 4 May, Danmarks Radio rebroadcasts the “message of liberation” for about an hour after 20:00. The original 4 May 1945 BBC Denmark broadcast announced the German surrender in Denmark.
Antenna setup
- The longwave antenna was a two‑tower Alexanderson aerial on the sea front, with two 118 m steel lattice towers connected by top capacitance wires. The northern tower was fed via a top coil; the southern tower was fed through the capacitance wires.
- The medium‑wave antenna was a single 147 m insulated lattice mast.
- All masts stood on the sea‑side Gisseløre peninsula, giving good radiation.
This page was last edited on 2 February 2026, at 17:48 (CET).