Analog Telephone Physics
April 15, 2023
Talk given at the Spring Meeting of the Indiana Section of AAPT in April, 2023.
Abstract
The analog telephone is quite an elegant circuit. We will discuss this circuit and some of the old analog switching mechanisms at the telephone office. We will also talk about the practice of ‘phone phreaking,’ the precursor to modern computer hacking, in which (mostly) high school and college kids learned how to manipulate the phone system in ways it was never intended to work.
Background
I got interested in this topic by reading Exploding the Phone: The Untold Story of the Teenagers and Outlaws Who Hacked Ma Bell. Also, in preparing this talk, I relied heavily on John Hearfield’s explanation and circuit diagrams.