Abstract: Multi-channel transmission systems make great demands on the adjustment of the local oscillators in order to minimize carrier frequency variations on the transmission and reception sides. There are prior art processes and arrangements in which the local oscillators are adjusted by means of a synchronism word. The prior art processes and arrangements, however, have the drawback that the oscillators cannot be adjusted accurately enough. The present invention overcomes this drawback in that, in addition to the known synchronism symbols, other synchronism symbols are used and the synchronism symbols are evaluated with increased spectral resolution.