求翻译：在信号极弱小时，使用了专用的差分放大器、可编程滤波器等电子仪器进行捕捉，并在示波器上显示，最终在仪器下至600米处，地面接收不到信号。是什么意思？

When the signal is very weak, with a dedicated differential amplifier, programmable filters and other electronic equipment to capture and display on the oscilloscope, the instrument down to the final 600 meters, the ground receiving the signal.

When the signal is very weak, and use the exclusive use of the differential amplifier, programmable filters to capture, and electronic equipment including the oscilloscope display on the apparatus, and eventually to 600 meters under ground, receiving no signal.

Is extremely small and weak when the signal, used special-purpose electronic instrumentations and so on differential amplifier, programmable filter has carried on the capture, and demonstrated on the oscilloscope, finally under instrument to 600 meters place, ground receive not to signal.

When the signal is very weak, use special differential amplifiers, programmable filters, and other electronic equipment to capture, and displayed on the oscilloscope, eventually under the instrument to 600 metres, the ground signal was not received.

When the signal is extremely small and weak, used the specialized difference to divide electronic instruments such as the amplifier, programmable electric-wave filter,etc. to catch, and reveal on the oscillograph, in the instrument to 600 meters finally, can not receive signals on the ground.