Portable grain analyzers are used for analyzing grain protein, moisture, and oil concentration critical to the profitability of each harvest. It is specially designed for rugged in-the-field use and can be operated without problem on the combine, tractor, pickup or while walking around the field. Its total solid state design uses no motors, no gears, no light bulbs or other mechanical devices that are failure prone. It displays protein and oil both on a constant moisture (CM) basis.