What is the first step for testing a completed PCB?

The first step in testing a completed PCB is to visually inspect component alignment and values. This initial inspection is crucial because it allows you to identify any potential issues before applying power to the board. During this visual check, you can ensure that all components are correctly placed, oriented properly, and that the component values (like resistors and capacitors) match the design specifications.

Looking for soldering issues, such as cold joints or bridges between pads, can also prevent damage that might occur if the board was powered without proper alignment. This foundational check is beneficial for detecting problems that can be easily fixed before proceeding to more complex tests, such as measuring the power supply input or checking for shorts. Therefore, starting with a visual inspection helps ensure that the board is ready for further testing phases without risk of failure due to assembly errors.