On the QSO content of the First Byurakan Survey and the completeness of the Palomar Green Survey

The second part of the First Byurakan Survey is aimed at detecting all bright (B < 16.5) UV-excess starlike objects in a large area of the sky. By comparison with major X-ray and radio surveys we tentatively identified as QSOs 11 FBS objects. We made spectroscopic observations of nine of them. We found six new QSOs bringing the total number of known QSOs in this survey to 42. By comparison with the Palomar Green (PG) QSO survey, we found that the completeness of this last survey is of the order of 70% rather than 30-50% as suggested by several authors.