PCB sensitization

In the middle of pcb sensitization is the old version of the gold board (TwT has expired), the left is the new version of the circuit board. On the far right is a ferric chloride block. Below is the photographic printed circuit board developer.

Modifying the pcb sensitization circuit diagram. Note: The following lights are turned off due to the sensitivity of the photographic pcb sensitization board to light. Using the utility knife plus steel ruler to draw the area you need on the photosensitive circuit board, and draw a few times with more force.