Dictaphone

Jamie McCrimmon was fascinated by gadgets such as Polly's secretarial dictaphone, on which she kept his recordings for many years after their travels. (AUDIO: The Forbidden Time)

In 1969, the Tenth Doctor recorded an alien signal at Mission Control with a dictaphone, and then was arrested. After the Doctor escaped several days later, he used the TARDIS to translate the recording into a visualisation of the sounds so he could communicate with the aliens. (PROSE: Blue Moon)