The 711B was donated to the engineering school back in the late 60's, and somehow found it's way to the station, where the station engineering department installed it, much to the annoyance of the telco (Pacific Telephone at the time).
I think that's cool the step system is still working. That's neat how you can patch audio through the switch, although as you said the audio might not quite be 30-15khz. It was almost like those step COs had character back then, the dial tones & ringing signals varied with different offices, and even slight differences could be heard with the same "model" CO. I'd like to find history book about Central Offices & telephony development in general.
