Aircheck

In the radio industry, an aircheck is generally a demonstration recording, often intended to show off the talent of an announcer or programmer to a prospective employer, but mainly intended for legal archiving purposes. A scoped (short for "telescoped" - by analogy with pressing the ends of a hand-held telescope to reduce its size) aircheck usually contains only segments where the announcer is actually talking, along with a bit of the music or commercial on either side. In an unscoped aircheck, all programming is left intact and unedited, including music, commercials, newscasts, jingles and other on-air events.

Another category of airchecks are those recorded "off-the-air" by listeners, using consumer or semi-professional equipment. These airchecks became more common with the advent of commercial cassette recorders.

One of the oldest known surviving airchecks consists of a 15-minute broadcast by Bing Crosby on Los Angeles station KHJ and the CBS network from September 2, 1931. It was recorded by the RCA Victor company of Hollywood and is fully documented in the Victor files at the National Archives. The recordings were made by RCA Victor at the request of rival network NBC, which apparently wanted to monitor the then-rising young singer. The sound of the recording suggests that it was made by placing an open microphone before a high-quality radio (a method known in the radio trade as a "mic-feed"). This recording is available online at Reelradio [1].

Airchecks can be recorded directly off the air (from a tuner or modulation monitor), from the pre-air feed that goes into the transmitter (which has usually been modified by the station's processing), or directly from before the station's processing has been applied.

Some radio stations used "logger reels" for airchecks. On these large reels of tape would be recorded the air signal at super-slow speeds. These reels were kept by the station for regulatory purposes (e.g. to provide an audio record that commercials ran as logged or to confirm aired content after allegations of inappropriate content). After a time, normally around 30 days for most stations, these logger reels would be reused or discarded.

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