Observations of the Structure of Radio Sources in the 3C Catalogue--III: The Absolute Determination of Positions of 78 Compact Sources

Observations have been made with the Cambridge One-Mile telescope of 78 unresolved or slightly resolved radio sources in the 3C catalogue. Absolute positions have been determined for these sources with typical errors of $$\sim 1^{\prime\prime} - 1.5^{\prime\prime} \,\text{arc in R.A. and} \,\sim 2^{\prime\prime} \,\text{cosec} \,\delta$$ arc in declination. Details of possibly associated optical objects are given.