Chapter 2: Components and Circuits #

In the previous chapter, you learned how voltage, current, and reactance interact in AC circuits. Now it’s time to meet the physical components that make those principles work—the building blocks inside every transceiver, amplifier, and power supply in your station.

As a Technician, you encountered basic components like resistors, capacitors, and diodes. Moving to General class operation, you’ll discover how these familiar parts behave differently at radio frequencies, and you’ll meet new components like MOSFETs, switching power supplies, and MMICs that enable modern radio performance. You don’t need to fully understand everything. We’ll give you a basic foundation so you know what’s available and which terms to use when you need more information.

You’ll learn how transistors and tubes amplify signals, how power supplies convert household AC into DC, and how digital circuits process information. Schematic symbols then let you follow the connections between those components, while measurement principles explain how to compare a circuit’s behavior with what you expect. Choosing and using instruments for station tests comes later, in Chapter 7.

Knowing power supply operation explains that hum in your audio. Recognizing RF component behavior reveals why some parts work perfectly at audio frequencies but fail at VHF. Even if you never design circuits from scratch, this knowledge helps you make informed equipment choices, understand specifications, and troubleshoot problems intelligently.