http://www.youtube.com/watch?v=xZePwin92cI

=======================

That 1951 clip is the best visual explanation I've seen of the SXS concept. Very cool.

Here is a film produced in 1974 that shows the manufacturing process for a 1ESS switch, the design AT&T first released around 1968 for serving larger metropolitan areas.

http://www.youtube.com/watch?v=8uMbpaFp3i4

Although the 1ESS was an electronically controlled switch, the signal path through it was still entirely analog. The computer portion was used to centralize diagnostic results for operators via a 300 baud teletype terminal, collect call billing detail for writing to tape, and manage the data for line and trunk routing in the switch. The "fabric" of the switch that connected lines and trunks together for calls was a giant tapestry of relays and wires. The quality with which the MILES of wire were connected and neatly laced down to the relay rack frames was a work of wonder to behold. (see 4:25) Here's a short film clip of the installation of some of the 1ESS switches installed at the World Trade Center buildings (see around 2:00).

http://www.youtube.com/watch?v=q1zg2l3WmeM


WTH