(Received January 10, 1985)
In order to obtain an ultrasonic power propagating through an ultrasonic transmission line, standing wave ratios of the longitudinal vibration are measured with a toroidal magnetic type vibration detector. A new power measurement technique is also proposed in which the particle velocity and the force at a nodal point are measured with the same detector. These results are compared with the powers measured by the power meter method. An ultrasonic power propagating in a bending vibration bar is also measured.