The attachment, 890966 D01 Level Probing Radar v01r01, provides guidance on making measurements for devices operating under Section 15.256.

The attachment, TR14-1007 Measurement of FMCW, provides background information on the derivation of the method for calculating the average of FMCW LPR transmissions and measurements confirming the calculated results.

Note: As an alternative to the provisions of Section 15.256 (See: Section 15.31(q)), an LPR may be certified under Part 15 for use solely in a metal or concrete tank by showing compliance with the provisions of Section 15.209 as measured outside the tank with the LPR installed inside the tank according to measurement procedures in ANSI C63.10, in lieu of the attached measurement procedure.