According to principle of measurement that metals with different internal lattice structures and diversity

corresponding structure frequency characteristics is different and has diversity

a kind of testing system that can fastly measure frequency characteristics of metals is designed based on C8051 F020 system on chip（ SoC）system. This testing system uses direct digital synthesis（ DDS） to generate excitation sine signals of continuous frequency conversion; detection the output signal of eddy current sensor

signal conditioning circuit decompose detected signal into two channels signal of amplitude and phase difference; computational analysis part of this system will estimate that whether the frequency characteristic vector value of the tested metal material conform to that of standard metal material

this system can detect non-destructively metal mass

but also can qualitatively analyze composition of alloy material or composite material

this testing system has extensive application value.