An end user can sample a radio or television broadcast, generate a user representation of the broadcast sample, and send the user representation to a comparison system, which also receives known representations of content broadcast by multiple different stations. The known representations are stored in a continuous fashion, and represent actually broadcast content. The comparison system identifies the source of the broadcast sample by comparing the user representation to the known representations associated with each of the different stations using a bit count method, such as the Hamming distance. By comparing two representations of content that was actually broadcast, a broadcast source can be identified without requiring the use of watermarks, timestamps, or a database of discreet content items.