The Strowger Switch

Good References:

The Theory of Electromechanical Switching
The Strowger Telecomms Page
Strowger or Step by Step Exchanges: The Principles
Switching and Transmission

Biselective Strowger Switch Operation (source) See a nice animation of switch operation at Final Selector
A Simple Example of Strowger Switch Implementation of Basic Switching Functions
A More Complete Example of Strowger Switch Operation (Dialing 3123) s
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