Interference from External High-Frequency and Ultrasonic Sources

Abstract

In order to correct internal faults of ultrasonic instruments, only the relevant service instructions should be consulted. In the case of external interference, however, certain remedies of general validity apply. If several adjacent pulse-echo instruments with not exactly identical repetition frequencies are used, the pulses are transmitted from one instrument to the other electrically and they travel across the image. This requires synchronisation of the repetition frequencies of the instruments concerned and instruments designed for use in testing installations are usually equipped with this synchronisation facility. If not installed, synchronisation is usually possible by slightly changing the wiring and for this purpose it is recommended to consult the manufacturer.