A 230 GHz SIS receiver for SEST

We describe a low-noise 230 GHz SIS receiver built for use as a facility instrument at the Swedish-ESO Submillimeter Telescope (SEST) on La Silla, in the Chilean Andes. The mixer block is a simple but proven design with a single tuning backshort. An elaborate system of control electronics permits remote and highly automated tuning. Receiver performance in the lab and on the telescope are discussed, and some initial spectra from astrophysical sources are presented