FCC Question Pool Review

Technician Class (Element 2) • 2022-2026

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Question T6B09

From subelement T6 - T6B

T6B09
Answer: C

What are the names for the electrodes of a diode?

APlus and minus
BSource and drain
CAnode and cathode
DGate and base

Why is this correct?

A diode has two electrodes: anode (positive terminal) and cathode (negative terminal, often marked with a stripe). These are the standard semiconductor terms. 'Plus and minus' are generic battery terminals, 'source and drain' belong to field-effect transistors, and 'gate and base' are transistor control electrodes.

Memory tip

Remember electrode names follow the component type: diodes use anode/cathode, bipolar transistors use emitter/base/collector, and FETs use gate/source/drain. Each semiconductor family has its own naming convention based on function and historical development.

Learn more

In amateur radio circuits, diodes serve critical functions like rectification in power supplies and signal detection in receivers. The anode receives conventional current flow while the cathode blocks reverse current flow. Understanding proper electrode terminology helps when reading schematics and troubleshooting equipment. Many RF circuits use diodes for switching, mixing, and protection—knowing anode/cathode orientation prevents damage during construction and repair.

Think about it

Why do you think different semiconductor components use completely different names for their terminals instead of standardizing on 'positive' and 'negative'?