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This used to not be safe though, in the age of landlines.

I forget the details, but most of the country was wired in a manner that both parties of a call had to hang up to end the connection.

You might hang up, go find the official phone number, but when you pick the phone off the cradle you would still be in the previous call. They could fake the dial tone and you would be none the wiser.

I remember pranking friends with this back when I was young. Harmless stuff.






I think this was in crossbar switches. The initiator of the call had to hang up for something like 8 seconds.

This was useful if they called you and you answered in the kitchen, but wanted to run to another room to talk. Not that I think it was designed to be a feature! But I used it that way.

If you didn't trust the caller, you could hang up, wait 10 seconds, then get a good clean real dial tone. Remember dial tones?

Anyway none of this is relevant in modern switching systems, much less cellular networks.


> The initiator of the call had to hang up for something like 8 seconds

Sorry, correcting myself:

If the initiator of the call hung up, the call would be ended immediately.

If only the receiver hung up, the call would remain "live" and resumable for about 8 seconds.


Thanks for that bit of history. I seem to remember form previous conversations with people that this was not the standard for all of America. Probably something related to east cost vs west coast.

> east cost vs west coast

More likely population density/growth in the region. Most of the US was all Bell System at the time.

If the area was urban, or growing quickly (adding new phone subscribers), they'd get the newer electronic (ESS) switches first, starting around the early 1970s.

If the area was suburban and population-stable, the electromechanical crossbar switches would live on for another 20+ years.

There were some rural parts of the US using even older Strowger/SxS switches until the mid 1980s at least, probably later!

There's a great story about the development, by a Mr. Strowger, of the first electromechanical telephone exchange switch. Previously, calls were connected manually, by operators. Mr. Strowger was an undertaker, and he believed that the operators were sending callers to his competition unfairly. So he invented an automatic switch to remove the human element.


> There's a great story about the development, by a Mr. Strowger, of the first electromechanical telephone exchange switch. Previously, calls were connected manually, by operators. Mr. Strowger was an undertaker, and he believed that the operators were sending callers to his competition unfairly. So he invented an automatic switch to remove the human element.

I’ve heard this one before. Wasn’t the wife of one of his competitors actually the operator in question?




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