In this paper, measurement results from an informal comparison among NIM, NMC and SCL, for primary power system with Type-N coaxial connector, are reported. This comparison aims to demonstrate the precision measurement capabilities and validate the equivalence of new replacements of Type-N microcalorimeters (for aged ones) at the participating laboratories. A commercial coaxial reference standard, thermistor mount, is used as the traveling standard, for the measurements from 10 MHz to 18 GHz. Generally, good agreements have been observed among the measurement results.