The sinusoidal signal generated by the signal generator is amplified by Aetna ata-105 power amplifier and loaded on the piezoelectric ceramic transducer to drive the piezoelectric ceramic transducer to vibrate at high frequency.

Screen the sensitive frequencies of multiple measurement targets, and adopt multi-frequency technology to alias multiple optimal excitation signals into a synthetic excitation signal, which is amplified by the power amplifier? and loaded on the detection probe; the leakage magnetic field near the defect is picked up by the magneto-sensitive element. , to characterize defects.

Detection process: The signal generator outputs a voltage of a certain frequency and waveform, and the power amplifier amplifies the voltage output by the signal generator, so that the system replaces the single drive coil with the uniform strength of the drive coil (the drive coil and the drive magnetic core).

According to the acoustic vibration test, a force hammer is usually used to excite the fruit samples. In order to reduce the signal interference and obtain a strong excitation response signal, a high-voltage amplifier is used to linearly amplify the Ve signal. Considering that the rated voltage that the sensor can withstand in continuous operation is 90V, the voltage signal is linearly amplified into an excitation signal VE with a pulse peak voltage of 80V, and then the sample is vibrated by the piezoelectric beam sensor at the excitation end.

The ATA-7000 power amplifier ?has a maximum output voltage of 6KVp-p, a maximum output current of 30mAp, and a bandwidth (-3dB) of up to DC~5KHz. It is widely used in ultrasonic resonance spectroscopy technology in the performance characterization of piezoelectric materials to meet the needs of different indicators.

The dry coupling Lamb wave detection hardware system is mainly composed of dry coupling probe, arbitrary signal generator, power amplifier?, multi-channel oscilloscope, computer and corresponding detection software.