Your Guide to Railway Signals
By Frederick J. Aubertin.
Softcover, 9x11", 370 pages. 2019.
"This is the book for you if you strive for railway signaling knowledge.
"Includes chapters on Track Circuits, Basic Crossings, Gate Crossings, Microprocessor-Based Crossings, Switch Circuit Controller (SCC) and Electric Locks, Switch Machines, Relay-Based and Processor-Based CTC, and Testing Locking Circuits."