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Practical repair guide for Sinclair QL keyboard membranes with broken circuit traces. Describes using a VOM ohm meter with an attached razor-blade probe to locate breaks through the plastic laminate by piercing the surface along the trace. Covers two failure modes: a single broken trace (repaired by exposing the area, bridging with aluminum foil strip and conductive paint, and covering with clear adhesive tape), and the more destructive cracking of all traces at the membrane/ribbon junction caused by adhesive solvent depleting the plastic’s plasticizer (repaired by securing ribbons with conductive paint and tape reinforcement).