The veterinary B-ultrasound image defect caused by the damage of the excitation pulse generating circuit. This circuit is mainly set on the integrated circuit board. When the ultrasonic excitation pulse measured on the integrated circuit board by the oscilloscope is abnormal or less than 20 pulse signal outputs, the pulse signals on the 20 output diodes on the integrated circuit board should be measured. If the waveform is abnormal, the working voltage of the switch field effect tube can be measured with a multimeter, and the static and dynamic DC working points can be observed by using the freeze key of the veterinary B-ultrasound host. In this way, the source of the fault can be found. The circuit failure is usually caused by the failure of the switch field effect tube or the deterioration of the corresponding drain resistor, which makes its resistance value tend to infinity. When it is confirmed that there is damage to the component, just replace the accessories with the same parameters. On the contrary, if all the output excitation pulses of the veterinary B-ultrasound circuit are measured to be normal.

The image defect caused by the damage of the veterinary B-ultrasound ultrasound receiving circuit. This circuit is mainly set on the integrated circuit board. When the high-voltage switch control pulses, excitation pulses, and excitation pulses output after control are measured on the integrated chip port on the veterinary B-ultrasound board, the relevant circuits on the receiving circuit board should be detected. An oscilloscope can be used to directly measure the waveform and voltage of the input and output ends of the 20 input coupling capacitors in the circuit. The failure of this circuit is mostly due to damage or degeneration of components on the veterinary B-ultrasound host circuit board, which causes high voltage electricity to leak into the receiving circuit, causing the coupling capacitor to deteriorate and leak electricity, and causing damage to the corresponding integrated circuit. When any of these components is damaged, the received signal cannot be transmitted to the lower-level circuit, resulting in the loss of veterinary B-ultrasound image signal.

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