FCC Question Pool Review

Technician Class (Element 2) • 2022-2026

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Question T6B02

From subelement T6 - T6B

T6B02
Answer: C

What electronic component allows current to flow in only one direction?

AResistor
BFuse
CDiode
DDriven element

Why is this correct?

A diode allows current to flow in only one direction, like a one-way street for electricity. Resistors limit current but allow flow in both directions. Fuses protect circuits by breaking when current is too high, but also conduct bidirectionally until they blow. A driven element is an antenna component, not related to current direction control.

Memory tip

Remember the 'di-' prefix means 'two' - diodes have two electrodes (anode and cathode) that create the one-way current path. When you see questions about directional current flow or rectification, think semiconductors, specifically diodes.

Learn more

Diodes enable rectification - converting AC to DC by allowing current flow only during positive half-cycles. The cathode (marked with a stripe) must be negative relative to the anode for forward bias conduction. This property makes diodes essential in power supplies, signal detection circuits, and LED indicators throughout amateur radio equipment.

Think about it

Why do you think the one-way current property of diodes is essential for converting the AC power from your wall outlet into the DC power your radio needs?