Measurement of Effective Temperatures of Microwave Noise Sources

This report describes a system now in operation for the purpose of calibrating microwave noise sources at three selected frequencies in the range 8.2 to 12.4 Gc. Included are a discussion of the reference standard noise source, an error analysis of the standard source and the comparison system, and evidence of system performance. Results of measurements indicate that the excess noise ratio of a specific commercial argon filled noise source is 15.6 db at 9.8 Gc. A calibration service is now available for tube-in-mount noise sources at the three selected frequencies 9.0 Gc, 9.8 Gc, and 11.2 Gc.