故障现象一：超声图像区内和灰阶棒不正常。灰阶棒上出现一段白一段黑间隔不等的干扰，整个超声图像区内有白色噪点干扰，字符、体标、测量、Ｂ、Ｍ、单双幅等所有功能均正常显示和转换。故障分析和处理：首先测量各直流供电电压，测得各直流电压均正常，可见故障原因不是由电 Symptom 1: The ultrasound image area and grayscale rod are abnormal. There is a white, black and black interval interference on the gray scale bar, white noise interference in the entire ultrasonic image area, and all functions such as character, body mark, measurement, B, M, single and double images are normally displayed and converted. Fault analysis and processing: First, measure the DC supply voltage, and measure the DC voltage is normal. It can be seen that the fault is not caused by electricity.