Beginners can follow these steps to observe and understand the board:

1. Observe the overall structure: First, carefully observe the overall structure of the circuit board. A circuit board usually consists of one or more printed circuit boards (PCBS) with many electronic components and wires on them. Pay attention to the shape, size, and color of the board, as well as the markings and labels on it.

2. Identify electronic components: Try to identify various electronic components on the circuit board. Common electronic components include resistors, capacitors, inductors, diodes, transistors, integrated circuits, etc. These components usually appear on the board in different shapes, colors, and markings. Use component specification sheets and marker readings to help you identify them.

3. Trace the circuit path: Trace the wire path on the circuit board to try to understand the connection mode of the circuit. Pay attention to the direction and connection of the wires. Try to trace the circuit path, from one component to another, and the connections between them. This helps to understand the signal flow and signal processing of the circuit. Pay attention to the width and shape of the wires, they may have different functions, such as transmitting power, signals, ground wires, etc.

4. Analyze the level of the circuit board: a complex circuit board is usually composed of multiple levels. By observing the structure and level of the circuit board, the function and design of the circuit board can be inferred. For example, multilayer PCBS are commonly used for isolation of high-density circuits and signal layers from power layers. By observing the layered structure of the circuit board, the design intention of the circuit board can be preliminarily understood.

5. Read board markings: Boards often have markings, labels, printed text, or ICONS that indicate components, connections, or other important information. Read these marks carefully, they may contain important information about the component model, value, polarity, connection mode, and so on. This helps to better understand the function and design of the board.

6. Refer to circuit diagrams and documentation: If possible, obtain circuit diagrams or related documentation for the circuit board. A circuit diagram is a graphical representation of a circuit on a board that can provide more detailed information. By comparing the circuit diagram with the actual circuit board, the structure and function of the circuit board can be better understood.

7. Learn basic circuit knowledge: In order to better understand the circuit board, it is recommended to learn some basic circuit knowledge. Understanding the basic concepts of current, voltage, resistance, capacitance in a circuit, as well as common circuit topologies and circuit analysis methods, will help you better understand how a circuit board works.

In the actual work, beginners should be based on practice and improve their circuit understanding ability by observing and analyzing actual circuit boards. As you gain experience, you will be able to more accurately understand and analyze the function and design of the board.