THE BRITISH RAILWAYS’ NEW SIGNAL BOX at Rugby, on the Euston-Crewe main line, which is one of the busiest in the world. The movement of each train, over 159 miles of track, is recorded on an illuminated wall chart 25ft long. A train records its presence when its steel axle conducts, at a low voltage, current from one rail to another. Instantly, a row of red lights on the chart marks the train’s position. The signalman, by pressing buttons on a keyboard, operates signal lights on the ground. The passing train automatically leaves a trail of red, yellow, and finally green signals. The new box replaces 22 manually-operated boxes and is claimed to be more advanced than any Continental or American signal box.

Press, Volume CIV, Issue 30640, 5 January 1965, Page 10

THE BRITISH RAILWAYS’ NEW SIGNAL BOX at Rugby, on the Euston-Crewe main line, which is one of the busiest in the world. The movement of each train, over 159 miles of track, is recorded on an illuminated wall chart 25ft long. A train records its presence when its steel axle conducts, at a low voltage, current from one rail to another. Instantly, a row of red lights on the chart marks the train’s position. The signalman, by pressing buttons on a keyboard, operates signal lights on the ground. The passing train automatically leaves a trail of red, yellow, and finally green signals. The new box replaces 22 manually-operated boxes and is claimed to be more advanced than any Continental or American signal box.