British broadcasting regulator Ofcom is letting AM stations go wider. That’s one of the decisions in its statement on the newly renamed “Analog Radio Technical Code.” The statement comes in response to public comment received as part of the review process begun in January 2024.
The statement marks the first major update to the code since it was put in place in 2013.
Currently, the U.K. authorizes AM services (531–1602 kHz) to operate with an audio bandwidth of 6 kHz. Under the updated rules, AM broadcasters can seek approval to adopt a wider audio bandwidth. To minimize the potential for interference, including interference with broadcasters outside of the United Kingdom, Ofcom will continue to require sideband limits of ±9 kHz, but will consider on a case-by-case basis relaxing the sideband limits at ±7.5 kHz.
Of the four groups commenting on the proposal, all were in favor of the move, though two argued for allow audio bandwidths as wide as 12 kHz, which Ofcom stated could cause problems with frequency planning and coordination.
All of the commentors noted that allowing for wider AM audio bandwidth could improve audio quality for listeners. The cost for broadcasters to implement a wider audio bandwidth was judged to be minimal, unless the station used a narrow bandwidth antenna or older audio processing equipment.
While most of the other changes were largely editorial, including renaming the “Ofcom Site Engineering Code for Analogue Radio Broadcast Transmission Systems” to the “Analog Radio Technical Code,” there were a few additional measures that broadcasters will need to accommodate.
All analog broadcasters are now required to “consider the end-to-end resilience of their services.” They are also required to have continuity plans in place in case a failure occurs. Ofcom is not requiring these plans be filed with the agency, but in the event of a major service failure the regulator will examine them as part of any investigation. This new requirement parallels a reseiliency requirement already in place for digital radio and television operators.
Also, absent compelling reasons, Ofcom will no longer conduct technical acceptance checks on new or modified transmitter installations. Instead, licensees will have to carry out their own tests and submit the results to Ofcom. This brings the practice for analog transmitters into line with the approach used for digital radio transmitter acceptance.
Ofcom also removed a requirement for directional couplers when a single transmitter is feeding an antenna system.
As part of the continued post-Brexit disentangling of the U.K. from European Union rules, Ofcom is also removing references to CE marking, which indicates a product that meets European standards and regulations. The British government intends to eventually replace CE marking with a UKCA accreditation mark.
Instead of relying upon CE marks to indicate compliance, under the update Ofcom requires licensees to “satisfy themselves” that their equipment meets all relevant standards.
The full statement, comments received, and other documents are available on the Ofcom website.
