U/D Ratio Calculator

About the U/D Tool

The U/D Tool is for use with the FCC's translator interference process outlined in §74.1203(a) and §74.1204(f). The tool uses various calculations to determine the service contour of a listener in respect to a 'desired' station as well as determining the interfering contour to an 'undesired' station. This tool should be used by an incumbent station to determine if an interference complaint brought on by a listener claiming interference from a new FM translator application or authorization could be actionable under the rules. It does this by calculating the 'undesired to desired' (U/D) ratio of both stations at the listener's location. The U/D calculation is only one of a few steps necessary to qualify a listener complaint.

You will need the Application ID numbers for both the desired and undesired stations. You can find those application ID numbers at fccdata.org.