  We continue the QSO search in the 10 square degrees Schmidt field around M92
based on variability and proper motion (VPM) constraints. We have re-reduced
162 digitised B plates with a time-baseline of more than three decades and have
considerably improved both the photometric accuracy and the star-galaxy
separation at B>19. QSO candidates are selected and marked with one out of
three degrees of priority based on the statistical significance of their
measured variability and zero proper motion. Spectroscopic follow-up
observations of 84 new candidates with B>19 revealed an additional 37 QSOs and
7 Seyfert1s. In particular, all 92 high-priority candidates are
spectroscopically classified now; among them are 70 QSOs and 9 Seyfert1s
(success rate 86%). We expect that 87% (55%) of all QSOs with B<19.0 (19.8) are
contained in this high-priority subsample. For the combined sample of
high-priority and medium-priority objects, a completeness of 89% is estimated
up to B_lim=19.5. The sample of all AGNs detected in the framework of the VPM
search in the M92 field contains now 95 QSOs and 14 Seyfert1s with B<19.9.
Although the VPM QSOs were selected by completely different criteria, their
properties do not significantly differ from those of QSOs found by more
traditional optical survey techniques. In particular, the spectra and the
optical broad band colours do not provide any hints on a substantial population
of red QSOs up to the present survey limit.
