What does "JA" Stands for on PCB?
It doesn't necessarily stand for anything. Markings like that are commonly used to indicate where a component goes on the PCB. Usually, the part is marked with some name, &quot;JA-1&quot; in this case, on the electrical schematic. This name is carried over to the PCB layout design as well so designers, layout people, assemblers, anyone working on the device knows what piece goes where.