Speedy Cutover Service, SXS switching cutover to ESS filmed live at Glendale CA central office, 1984

A brief but surprisingly exciting 1984 video showing the preparation and live, real-time cutover from Step By Step switching system (SXS) to a new electronic switching system (ESS) in Glendale, California.

Western Electric offered the Speedy Cutover Service to switching offices throughout the Bell System. Western Electric installers would visit a facility and prepare it, installing the new equipment inside the facility. They would identify and mark the existing cables that would need to be cut, then prepare employees for the cutover to the new ESS system.

Previously a cutover from step-by-step (or from crossbar service) to ESS would take many frantic minutes, upwards of an hour, during which time active telephone service would be lost mid-call. With the speedy cutover service – 51 installers simultaneously cutting 927 cables as fast as possible, all on cue – the interrupted service could be brought down to well under a single minute.

The climax here is unquestionably the moment of truth, the cutting of the cables, which is shown in real time. After making sure no emergency calls are underway, and with a shout of "Let's cut it!" the race is on, with three camera set-ups and a disco score capturing and preserving the moment of truth.

Footage Courtesy of AT&T Archives and History Center, Warren, NJ

Видео Speedy Cutover Service, SXS switching cutover to ESS filmed live at Glendale CA central office, 1984 канала AT&T Tech Channel