(1) Check the original appearance of the circuit board. Pay attention to cleanliness and appearance inspection.

(2) Inspect the mask, including specified color, specified thickness, quality defects, and pitting.

(3) Is electroplating sufficient? Adequate electroplating is difficult to measure. If the requirements are strict, the current requirement is based on the plating thickness.

(4) Is the hole centered around the pad (annular ring and alignment)?

(5) Is the hole size correct?

(6) Does the appearance match the artwork?

(7) Does the steel mesh match the printing position of the circuit board?

(8) Is the overall circuit board size correct?

(9) Is the PCB warped?

(10) Is there copper on the edge of the PCB board?

(11) PCB tracking width tolerance.