Towards an optical time scale at VNIIFTRI

A frequency chain for converting the frequency of an optical clock based on ultracold ⁸⁷Sr atoms is updated for its comparison with the frequency of microwave standards from the State Primary Standard of time and frequency units and the national time scale, GET 1-2018. The results of the corresponding experiments are reported and analysed. An instrumental complex for reproducing and keeping the time and frequency units and the national time scale of the primary standard is described; this complex includes an optical clock based on strontium atoms and microwave standards of new generation. The order of the atomic time scale generation with application of optical clocks is also determined.