During the 1970s, prior to the development of fiber optic transmission capabilities, the mesa's unrestricted views from San Diego County to Orange County made it the ideal location for a microwave relay station which was the backbone of telephone communications in the era. AT&T purchased on the top of Redonda Mesa from the Sharp Family Trust and in about 1981. The company built a high tower with numerous white cones pointed toward transmission and receiving stations in the Oceanside and San Clemente areas. The tower served the region for about a decade and then fell into disuse as new technologies took over.