The WUTR has an article on the Teletype Model 28, a very popular machine recently discussed here. See:
On Nov 17, 1964, WU announced the completion of its 7,500 mile transcontinental microwave system. The system intentionally avoided cities by 30 miles by request of the Dept. of Defense for reliability in case of attack on a city. WU intended for the system to be used for AUTODIN (a Dept of Defense message communication system), and private line voice and broadband services.
WU touted a "push button" telephone to switch to different circuits. However, these were not Touch Tone phones. Rather, the push buttons activated various electrical characterists; to me, it sounded to the coding arrangement of Panel switch signals to the indicator lamps of a manual switchboard.