Compact components of several radio sources were observed in the course of VLBI observations at S-band between NASA-JPL Deep Space Stations located in Australia, South Africa and California, U.S.A., during the southern summer of 1971–72. These stations were equipped with H-maser frequency standards over this period so that the fringe frequency could be determined to better than 1 mHz.
The internal consistency of the position solution could be assessed for sources observed at least three times. This varied with source declination from ± 0″.1 at a declination of 45° to ± 2″.0 near the equator.
The spread in the position solution for P0727-11, a rapid variable at the observing frequency, was also large.
Positions obtained for some other sources have been used to assist in the identification of associated optical objects.