John F. Kennedy assassination Dictabelt recording

A Dictabelt recording from a motorcycle police officer's radio microphone stuck in the open position became a key piece of evidence cited by the House Select Committee on Assassinations (HSCA) in their conclusion that there was a conspiracy behind the assassination of John F. Kennedy on November 22, 1963. Made on a common Dictaphone-brand dictation machine that recorded sound in grooves pressed into a thin vinyl-plastic belt, the recording gained prominence among Kennedy assassination conspiracy theorists following the HSCA's 1978 conclusion, based in part on this evidence, that there was a "high probability" that Lee Harvey Oswald did not act alone and that the Kennedy assassination was the result of a conspiracy.

The recording was made from Dallas Police Radio Channel 1, which carried routine police radio traffic. Channel 2 was reserved for special events such as the presidential motorcade. The open-microphone portion of the recording lasts 5.5 minutes and begins at about 12:29 p.m. local time, a minute before the assassination. Verbal time stamps were made periodically by the police radio dispatcher and can be heard on the recording.