When the proposal was presented to the Reagan administration, two options were considered to build the radar systems: allow corporate bids to build the systems based on the schematics of the previously developed prototype radar or seek contractors to build their own systems using predetermined specifications. The JSPO group opted to select a contractor to develop and produce the radars that would be used for the national network. Radar systems developed by Raytheon and Unisys were tested during the 1980s. However, it took four years to allow the prospective contractors to develop their proprietary models. Unisys was selected as the contractor, and was awarded a full-scale production contract in January 1990.