| 摘要 |
PURPOSE:To prevent the noises onto a screen when a switching power source is used. CONSTITUTION:The power source device is used to supply a prescribed voltage to the Doppler ultrasonic diagnosing device for evaluating the vital function of a living body by ultrasonic pulses and has a PRF setting section 7, the switching power source 5, and a control circuit 6 for changing a switching frequency to the integer times of a pulse repetitive frequency. |
