 On 24 January 2009 , Ofcom allowed electrical retailers to be granted a licence to rebroadcast DAB signals within their stores to demonstrate DAB radio sets within their stores . The United Kingdom consumer charity , Which ? warned that consumers who could not get an adequate DAB signal could be misled by the in @-@ store sets . The Digital Radio Development Bureau replied to the Which ? report stating that stores contain a steel structure which produce a <unk> cage effect where DAB signals are blocked out . The DRDB recommended that consumers should check DAB coverage online with their postcode before purchasing a DAB radio to avoid disappointment . 
