Updated: Dec 9, 2025 | Source: 2023-2027 Question Pool | Topic: G6A
G6A06G6A

Why should wire-wound resistors not be used in RF circuits?

Deep Dive: G6A06

The correct answer is B: The resistor's inductance could make circuit performance unpredictable. Why wire-wound resistors should not be used in RF circuits is that the resistor's inductance could make circuit performance unpredictable. Wire-wound resistors have significant inductance that affects RF operation. For amateur radio operators, this is important for RF circuit design. Understanding this helps when selecting resistors.

Why Other Answers Are Wrong

Option A: Incorrect. Tolerance isn't the issue - wire-wound resistors can have good tolerance. The issue is inductance, not tolerance. Option C: Incorrect. Overheating isn't the specific issue - wire-wound resistors can handle power. The issue is inductance affecting RF performance. Option D: Incorrect. Internal capacitance isn't the issue - the issue is inductance. Wire-wound resistors have inductance, not problematic capacitance.

Exam Tip

Don't use wire-wound in RF = inductance makes performance unpredictable. Think 'W'ire-'W'ound = 'W'inding creates 'I'nductance. Wire-wound resistors have significant inductance that affects RF operation. Not tolerance, not overheating, not capacitance - just inductance.

Memory Aid

Don't use wire-wound in RF = inductance makes performance unpredictable. Think 'W'ire-'W'ound = 'W'inding creates 'I'nductance. Wire-wound resistors have significant inductance that affects RF operation. Use carbon or metal film for RF.

Real-World Example

You design an RF circuit. Wire-wound resistors have significant inductance from their coil construction, which can resonate with circuit capacitance or affect impedance at RF frequencies. This makes circuit performance unpredictable. Use carbon or metal film resistors for RF instead.

Source & Coverage

Question Pool: 2023-2027 Question Pool

Subelement: G6A

Reference: 2023-2027 Question Pool · G6 - Circuit Components

Key Concepts

Wire-wound resistors Inductance RF circuits Resistor types

Verified Content

Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G6A topic.