| 摘要 |
An echo-pulse tester comprises a synchronizer (5), one output of which is connected to one of the inputs of an indicating unit (9) and another input is connected to the input of a pulse generator (1). The output of the pulse generator (1) is connected to the input of an amplifier (4) and to one of the inputs of a filter (2), whose other input is connected to an ultrasonic converter (3) and the output is connected to an electronic switch (6) connected to a controlling input of a power supply unit (8). The output of the power supply unit (8) is connected to the corresponding inputs of the pulse generator (1), of the amplifier (4) and of the indicating unit (9). The tester is provided with a decimal echo-pulse counter (7) and with a pregnancy-determining circuit (10), the input of the amplifier (4) being connected to the corresponding inputs of the pregnancy-determining circuit (10) and of the echo-pulse counter (7), the outputs of which are connected to information inputs of the indicating unit (9). The output of the indicating unit (9) is connected to the other input of the pregnancy-determining circuit (10), the output of which is connected to the other input of the amplifier (4), whereas the other output of the synchronizer (5) is connected to one of the inputs of the echo-pulse counter (7), and the output of the power supply unit (7) is connected to the corresponding inputs of the echo-pulse counter (7) and of the pregnancy-determining circuit (10). |
