As shown in the picture, the J602 interface in the upper right corner of the picture is connected to a coaxial cable (I don't know if it is called a coaxial cable?). The signal line of the cable and the shell are short-circuited. The impedance measured with a multimeter is about 5 ohms. I think it is because the whole machine or the circuit board is not properly grounded, causing the signal line and the shell to short circuit? Because this is not one case or two cases. I would like to ask, how to check whether the PCB grounding is good?
Cecily postato su July 30, 2020
Check if the safety distance of the PCB is too small?
Glen postato su July 30, 2020
"The signal wire of the cable and the shell are short-circuited" There are many situations here, and every component in the signal wire cable path may be short-circuited to the ground. . .
Does the PCB grounding have anything to do with the short circuit of your cable's signal line and the housing? ? ?
Christa postato su July 30, 2020
The key is whether the ground wire of the power supply is connected properly, and is there any other interference?
