Anyone interested in the pre-digital switching can spend some very satisfying time at the Connections Museum. https://m.youtube.com/watch?v=Gsx2ZsYggGw&t=956s&

Anyone interested in the pre-digital switching can spend some very satisfying time at the Connections Museum. https://m.youtube.com/watch?v=Gsx2ZsYggGw&t=956s&pp=ygUSY29ubmVjdGlvbnMgbXVzZXVt https://m.youtube.com/watch?v=Gsx2ZsYggGw&t=956s&pp=ygUSY29u... The all mechanical switches are flat out amazing, and quite performant, given the tech. Often, it was less than a second from off hook to dial tone! The video I linked has some great detail. And they did not have amplifiers! One implication was surprising! Say you made a machine to generate dialtone. Great. It could service X number of subscribers based on its capability and Ohm's law. Want or need more? Get more or bigger machines. It is crazy! Another implication was each circuit needed to be ideal in order to carry voice. No amps meant a closed DC loop with the mic able to modulate voice via resistance. This is part of why the telcos resisted any attempt to connect to their network. It was easy to load it all down which required a service call Anyhow, I was quite surprised to learn how telephony worked and have appreciation and respect for the engineers and their work connecting the nation.