Millimeter and sub-millimeter astronomy plays an important role in the study <br />
of star formation, Galactic and extragalactic structure, stellar evolution, and <br />
astrochemistry. <br />
The Arizona Radio Observatory, which consists of two telescope facilities <br />
(Kitt Peak 12 m and the Sub-millimeter Telescope (SMT)), is an active contributor to these <br />
fields. Recent technical upgrades have been made to these instruments in the areas of <br />
receivers, spectrometer backends, and computer/system control. For example, an ALMA Band 6 mixer has been tested for the first time on the SMT. These upgrades will be described, as well as recent scientific results obtained as a result of such improvements.