The UV-B Monitoring and Research Program operates a national network of solar irradiance monitoring stations equipped with instruments which provide measurements to meet the needs of both agricultural and atmospheric researchers. Two of the instruments deployed in the network are unique since they provide the important and useful direct component of solar irradiance without the expense and complexity of a solar tracker. Instrumentation includes: - Ultraviolet Multifilter Rotating Shadowband Radiometer: Direct, Total Horizontal, and Diffuse UV Irradiance at nominal 300, 305, 311, 317, 325, 332 and 368 nano-meter wavelengths - Photosynthetically Active Radiation Sensor: 400 - 700 nano-meter wavelengths - Broadband UVB-1 Pyranometer: (280-320 nm, erythemal weighted for skin damage) - Multifilter Rotating Shadowband Radiometer: Direct, Total Horizontal and Diffuse Visible Irradiance at nominal 415, 500, 615, 673, 870, 940 nano-meter wavelengths, plus one unfiltered (open) silicon photodiode of 300-1040 nm. - Barometric Pressure Sensor - Air Temperature and Relative Humidity Sensor - Downward Looking Photometer - UV-A biometer All instruments have on-board data logging capability. Measurements are provided as 3-minute averages, aggregated from 15/20 second readings of each instruments' raw output voltage.