Deep Dive: T6B09
The correct answer is C: Anode and cathode. The electrodes of a diode are called the anode and cathode. The anode is the positive terminal (P-type material in a semiconductor diode), and the cathode is the negative terminal (N-type material), marked with a stripe on the package. Current flows from anode to cathode when the diode is forward-biased. This terminology comes from vacuum tube technology and has been carried over to semiconductor diodes. For amateur radio operators, understanding diode electrode names is essential when reading schematics, installing diodes in circuits, and troubleshooting equipment. The anode-cathode terminology is universal across all diode types, including signal diodes, rectifier diodes, Zener diodes, and LEDs.
Why Other Answers Are Wrong
Option A (Plus and minus): Incorrect. While anode is positive and cathode is negative, the correct terminology is 'anode' and 'cathode,' not 'plus' and 'minus.' These are the standard technical terms. Option B (Source and drain): Incorrect. Source and drain are the terminals of field-effect transistors (FETs), not diodes. Diodes have anode and cathode terminals. Option D (Gate and base): Incorrect. Gate is a FET terminal, and base is a bipolar junction transistor (BJT) terminal. Diodes don't have these - they have anode and cathode.
Exam Tip
Diodes have anode and cathode. Transistors have different names (gate/drain/source for FETs, base/emitter/collector for BJTs). If the question asks about diode electrodes specifically, the answer is anode and cathode.
Memory Aid
Diode = Anode and Cathode. Think 'A'node = 'A'ccepts current (positive), 'C'athode = 'C'ompletes circuit (negative, striped).
Real-World Example
When installing a rectifier diode in your power supply, you connect the anode (positive, unmarked end) to the AC input and the cathode (negative, striped end) to the positive DC output. This allows current to flow in only one direction, converting AC to DC. Understanding which end is anode and which is cathode ensures proper circuit operation and prevents damage from reverse connections.
Source & Coverage
Question Pool: 2022-2026 Question Pool
Subelement: T6B
Reference: 2022-2026 Question Pool · T6 - Electrical components
Key Concepts
Verified Content
Question from the official FCC Technician Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the T6B topic.