Full disk resonant scattering spectrometer providing radial velocity measurements of the Sun at the Potassium KI 769.9 nm line. It belongs to the HIROS (High Resolution Spectroscopy) group of the School of Astronomy and Physics of the University of Birmingham. Since 1993, it constitutes one the "nodes" of the BiSON (Birmingham Solar Oscillations Network). The others are located in Australia (2), Chile, California (USA) and South Africa.