Extragalactic radio source positions referred to the first USNO CCD Astrograph Catalog (UCAC1) are presented. They were derived from CCD observations taken with the 1.6-meter Cassegrain telescope at the Laboratório Nacional de Astrofísica, Brazil (LNA). The observations started in 1997 and were carried out in a joint program between USNO, Observatório do Valongo/UFRJ, Brazil, and Observatório Nacional/CNPq, Brazil. They were planned to provide, together with CTIO observations, fiducial points to link the UCAC to the ICRF. The results presented here refer to 24 radio source targets distributed mainly between −30° and −70° declinations. Reduction techniques follow standard procedures. The results are compared with VLBI and with similar precise optical positions, in order to contribute to the evaluation of the UCAC astrometry.