  We studied new simultaneous observations of the flux variations of the
photospheric and chromospheric emissions of 33 solar-type stars and Sun during
the HK-project that were conducted over the past 20 years. In addition to the
known cyclic chromospheric emission variations of stars at the 11-year time
scale, which were discovered at the Mount Wilson Observatory, we found a
recurrences that are similar to the quasi-biennial variations of solar
radiation. The results of calculations of the radiation fluxes variations
periods of stars at the quasi-biennial scale are given.
