Typical Transducer Testing
Typical transducer testing starts out with basic physical dimension measurements. Next, simple tests for continuity, shorts, opens, etc are performed. Simple electrical measurements such as capacitance and loss are usually made to ensure the device does not have any major defects after assembly. Next, functional testing is performed at ambient conditions. This usually consists of a pulse-echo measurement made in air or water at a specified distance and reflecting off a pre-determined target. The ring-down, bandwidth, and sensitivity are recorded. Often Total Acoustic Power output (TAP) is measured at this time. Finally, the device is put under whatever environmental conditions it is designed for and tested again.
The functional tests consist of driving the transducer with a sine wave, square wave, pulse or spike depending on the intended use. This is usually done with an industry standard pulser-receiver, sometimes through an amplifier. The pulse and return signal are viewed on an oscilloscope to make numerical measurements and to look at the subjective ‘cleanliness’ or ‘quality’ of the waveform.