 The TRC-97 provided data, voice and teletype connectivity for MTDS and would grow to become the backbone of USMC and USAF long haul communications for years to come.Early in the design phase of MTDS, it was decided to use magnetic drum memory computers.Memory drums were used as the digital storage elements and system clock pulse generators in the Central Computer Group and each of the Radar and Identification Data Processors (RIDP).