This repository contains code written by Paul Grimes to simulate a number of SIS mixer based receiver circuits and other microwave circuits. It incorporates the SuperMix library from CalTech in the library/ directory. Please see: http://www.submm.caltech.edu/supermix/ CalTech retains copyright of the SuperMix library, but allows distribution of source and binaries for non-commercial use. See the COPYRIGHT notice in the library/ directory.