Abstract
COMPASS is an on-axis 2.6 meter telescope coupled to a correlation
polarimeter. The entire instrument was built specifically for CMB polarization
studies. Careful attention was given to receiver and optics design, stability
of the pointing platform, avoidance of systematic offsets, and development of
data analysis techniques. Here we describe the experiment, its strengths and
weaknesses, and the various things we have learned that may benefit future
efforts to measure the polarization of the CMB.
