Deep Dive: E7D03
The correct answer is A: A Zener diode. What device is used as a stable voltage reference is a Zener diode. Zener diodes provide stable voltage references. For amateur radio operators, this is important for power supply design. Understanding this helps when designing regulators.
Why Other Answers Are Wrong
Option B (Digital-to-analog converter): Incorrect. DAC isn't used as voltage reference - Zener diode is. DAC isn't the device. Option C (SCR): Incorrect. SCR isn't used as voltage reference - Zener diode is. SCR isn't the device. Option D (Analog-to-digital converter): Incorrect. ADC isn't used as voltage reference - Zener diode is. ADC isn't the device.
Exam Tip
Device for stable voltage reference = Zener diode. Think 'Z'ener 'D'iode = 'Z'ero voltage change (stable reference). Zener diodes provide stable voltage references. Not DAC, not SCR, not ADC - just Zener diode.
Memory Aid
Device for stable voltage reference = Zener diode. Think 'Z'ener = 'V'oltage 'R'eference. Zener diodes provide stable voltage references. Important for power supply design.
Real-World Example
A stable voltage reference: A Zener diode is used. Zener diodes maintain a constant voltage over a range of currents, making them ideal voltage references. This is the device - Zener diode for voltage reference.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E7D
Reference: 2024-2028 Question Pool · E7 - Practical Circuits
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E7D topic.