Use of a sampling oscilloscope for velocity measurements and frequency comparisons of impulse acoustic surface waves

A simple method of phase-shift and velocity measurements of impulse surface waves in an active delay line is related. Using Lissajous´s displays on a sampling oscilloscope, accurate measurements are performed, even though the transmitted signal is disturbed by r.f. leakage, echoes or spurious modes. The same technique is applied to the frequency determination of a convoluted signal in a nonlinear device.