Telephone Central Office alarm sounds – visual and audio #Telephony @museumofcomm

A new YouTube video provides the signaling and alarm sounds for the types of alarms found in a old telephone central office (CO) has been posted by the Connections Museum.

Different alarms were used to mean different things in different offices. Much of it was up to local practice. The one thing that was always the same was the Major Alarm gong (MJ). That’s the first one you hear.

It’s worth noting that the panel office does not use these alarms, as it predates all of them. It has its own.

You can see the video (above). The audio file may be downloaded here.


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