General Introduction

The DAS (Digital Autocorrelating Spectrometer) is the main spectrometer backend for use with heterodyne receivers. It can be used for high resolution work, wide bandwidth observations or a combination of the two. Observing modes can be BMSW, PSSW, NSW or FSW, using any of the heterodyne receivers. Calibration modes can be BE (channel by channel), IF or FE, using 2-load or 3-load. Continuous raster (or ``on-the-fly'') mapping is also available. Cross correlation can be used for interferometry.