Membrane switchcores with key cell contact elements connected together for continuous path testing

In a membrane switchcore comprising a flexible plastic film substrate, a conductive first circuit including a plurality of conductive first traces and a plurality of conductive first contact elements connected to each first trace, and a conductive second circuit including a plurality of conductive second traces and a plurality of conductive second contact elements connected to each second trace, wherein a first contact element and a second contact element are at each key cell of the matrix and adapted to be bridged by a movable contact for actuation of a key cell,

• the improvement wherein:
• each first contact element consists of an integral section of its respective first trace;
• each second contact element consists of an integral section of its respective second trace;
• and
• each first trace and its respective first contact elements define a continuous conductive path, and each second trace and its respective second contact elements define a continuous conductive path.