An Interferometer for the Measurement of Radio Source Sizes

Abstract

Modifications have been made to the 85·5 Mc/s cross-type radio telescope at Sydney to permit the measurement of radio source sizes in the range of 10' to l' arc. The basic modification involves the addition of another aerial at a distant site connected by radio link. A new form of automatic gain control ensures very good stability for the system. The modified instrument is described in general terms and calibration techniques are discussed.