2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/35283It is shown that the general belief that the frequency and the absolute value of the velocity of periodic signals sent by a standard emitter do not change on the world line of the emitter needs to be revised and new conditions for the existence of a calibrted standard emitter should be taken into account. The notions of a standard clock and of a calibrated standard clock are introduced in a space with affine connections and metrics. The variation of the velocity and of the frequency of a standard clock could be compared with the constant velocity and the constant frequency of a calibrated standard clock along the world line of the observer. This calibrated standard clock is transported by meand of a generalized Fermi-Walker transport along the same world line of the observer. Some remarks about the synchronization of standard clocks in spaces with affine connections and metrics are given. PACS numbers: 95.30.Sf; 04.90.+h; 04.20.Cv; 04.90.+e18 pages, LaTeXGeneral Relativity and Quantum Cosmologytext