Air Traffic Control Voice Recorder Development.

The report summarizes the results of the Phase I study portion of a two-phase program designed to establish the technical base for development of two new, standard, multichannel voice recorder-reproducer sets. These sets are intended for use in recording the radio and landline communications at fixed and mobile Air Traffic Control ATC facilities. The basic problem is to provide a technically feasible, cost effective means of recording 80 channels of voice data on a single reel of magnetic tape for a period of 25 hours. The choice of head track geometry and multiplexing techniques emerge as the most critical factors affecting the design concept. A study of multiplexing techniques as affected by tape transport anomalies and signal conditioning characteristics is conducted in depth. Tape drive electronics are analyzed for performance at low speeds to optimize the recording time available for a given tape length. As a result of the Phase I study, the conclusion is that a recordreproduce tape speed of 1.2 inches per second should be utilized to record three 3 channels of the input voice data on each track of a 28-track headtape configuration, using a double sideband multiplexing technique. Author