Wireless network
Before the SBC Merger Ameritech sold some of its interests to GTE dba Verizon. Following the SBC Communications merger, Ameritech's wireless network was integrated and added to SBC's Wireless network. Originally Ameritech used CDMA as its network technology choice, but then converted to TDMA to be compatible with SBC's other wireless networks that were mostly using TDMA. During the SBC Communications merger its First and Original network in Chicago was sold to GTE (which later became Verizon Wireless).