A carbon-based composite particle for an electron emission source comprises a particle of a material selected from the group consisting of metals, oxides, and ceramic materials; and a carbon-based material such as a carbon nanotube which is partially embedded inside the particle and which partially protrudes from the surface of the particle. In one embodiment, an input voltage to a DAE is detected and a control signal corresponding to the input voltage is generated. The arrangement is such that the drive chain is guided into the chain wheel so that, as seen in the direction of movement, the connecting element in a leading coupling area of one plate link element is guided into an associated reception area of the chain wheel.