bellsystem

The PBX behind this looks like a Western Electric 702 (step-by-step, electromechanical) which were very popular in Pacific Telephone territory at the time. I have a tough time telling 701, 702, and 740s apart. Note that all 1970s-era Rohr Chula Vista images show rotary dials, suggesting step-by-step.

The plugs and jacks look like bantams rather than quarter-inch phone plugs. Do you agree?

In some installations, long distance calls tripped a mechanical counter. There would be a backboard with a bunch of mechanical counters. Each counter registered ZUM Units or something billable. Somebody from Pacific Telephone would come in with a Polaroid once a month and take photos. The photos would be how the user was billed.

You can almost hear that 600 Hz + 120 Hz dialtone...

If she were really "on the phone," one of the line buttons would be depressed and lit. Nice portrait anyhow.

These are apparently Rohr's effort to make horn antennas for the Bell System. These were an artifact of five nines reliability. Most of the 3500-4000 MHz links these carried have been transitioned to (reliable) fiber.

In a WalMart culture, where everyone is trying to get something for nothing, there's no room for five nines reliability.

Suggested reading: Sagan, Scott, The limits of Safety: Organizations, Accidents, and Nuclear Weapons

Installed horn antennas: