It looks a lot more exciting than pushing buttons on a terminal. There are bolt cutters and everything.

This is a telephone exchange 36 years ago moving 30,000 customer phone lines from an old mechanical system to digital in UNDER A MINUTE in Glendale CA.

The lady at the beginning is checking there are no emergency calls in progress before “the cut”. Weeks of preparation went into installing the new system ahead of time ready for switchover. 127ft (38709mm) of scaffolding was erected for 54 engineers to cut 927 large “trunk” cables in 47 seconds to avoid disrupting customers as much as possible.

The high demand for phone lines required rapid development in technology (similar to cellphone radios now I suppose) and resulted in amazing advances in electronics and computing.

From the AT&T Archives on YouTube