Coordinate switching matrix for telephone exchange - uses coils to magnetise strips with contacts at their crosspoints

摘要

The electronic telephone exchange switching matrix consists of two orthogonal sets of soft-iron strips (3-6, 7-10) with contact studs (11) or pins at their crosspoints. The ends of the strips in one set have coils wound around them and are joined to a first magnetic return rail (1). Similarly the ends of the strips in the other set have their own coils and are joined to a second magnetic return rail (2). The two rails are joined together. Coordinate switching signals are applied to the coils for strips magnetisation.