Two configurations of the instrument are shown above. The configuration for normal impact-echo testing is shown on the left. The configuration on the right shows two transducers fixed in a spacer bar and used for independent measurements of wave speed. The wave speed is determined by making an impact on a straight line between the two transducers and measuring the time required for the direct P-wave to travel the known distance between the two transducers. With a 7.5 lb. notebook computer, the system on the left weighs about 13 lb.
Power is provided by internal batteries in the notebook computer and data acquisition system.
A fully charged notebook battery typically provides 2 - 3 hours of operating time. The battery in the data acquisition system provides 8 hours of operating time when fully charged. One transducer unit is required for routine impact-echo testing. The second unit is used in measurements of wave speed, which are required for independent measurements of concrete plate thickness. It meets airline standards for carry-on luggage.