Initially the station was limited to Lisbon. On 6 October 2019, it started broadcasting to Porto on 98.4 FM.[3] On 21 January 2021, it started broadcasting to Aveiro on 88.1 FM, with the antenna located in São João da Madeira[4] and, on 19 March 2021, started broadcasting on 93.7 MHz in Amadora, increasing its coverage in the Lisbon area.[5] On 1 June 2023, Rádio Observador started broadcasting to the Ribatejo and the Western Region on 92.6 FM and 99.5 FM in Rio Maior.[6] On 12 July 2024 the station expanded to the Leiria region replacing Rádio 94FM and is in the process of buying Emissora das Beiras in Tondela.[7]