The dimmer works really well ... if he were not excited by the transformer of a light string. The twilight switch responds to the magnetic field of the power supply in addition to the Dimmer.Erst an aluminum surface 10x10 cm between shields the radiation off and then he works as he soll.Den same dimmer I have seen are in operation ... already more than 10 years if HAMA Dimmer also hold for so long .... or rather .... to keep (built-deficiency)