We present an organic device with an abrupt increase in the current when the applied voltage exceeds a critical value, behaving like a switch. The device consists in a blend of poly(acetoxy-p-phenylene vinylene) and poly(methyl methacrylate) sandwiched between two metal electrodes, one of them being Cu. The device construction is quite simple and the critical voltage can be controlled using different conjugated materials in spite of poly(acetoxy-p-phenylene vinylene).