Question T6C08
From subelement T6 - T6C
What is component 9 in figure T-2?
Why is this correct?
Component 9 in figure T-2 is a variable resistor, which allows you to adjust resistance by turning a shaft or sliding control. Variable capacitors, inductors, and transformers have different schematic symbols and functions. The context indicates this variable resistor limits output current in the power supply circuit, a typical application for adjustable resistance components.
Memory tip
Learn to distinguish variable components by their symbols: variable resistors show an arrow through the resistor symbol, variable capacitors have curved arrows near parallel plates, and variable inductors display arrows through coil symbols. The arrow always indicates the adjustable element.
Learn more
Variable resistors (potentiometers) are fundamental in amateur radio equipment for user controls like volume, gain, and tuning adjustments. They provide continuous resistance variation within their specified range, unlike fixed resistors. In power supplies, they serve as current limiters or voltage dividers. Understanding their schematic representation helps you read circuit diagrams for transceivers, amplifiers, and antenna tuners where manual adjustments are essential for proper operation.
Think about it
Why do you think a variable resistor would be specifically chosen over other variable components to limit output current in a power supply circuit?