Deep Dive: T5B12
The correct answer is D: 28.400 MHz. 28400 kHz equals 28.400 MHz. To convert kilohertz to megahertz, divide by 1,000. The prefix 'kilo-' means one thousand, and 'mega-' means one million, so 1,000 kHz = 1 MHz. 28,400 kHz ÷ 1,000 = 28.4 MHz. This is a standard frequency conversion. 28.400 MHz is in the 10-meter amateur band. Understanding these conversions is essential for frequency calculations and band identification. Both notations (28400 kHz and 28.400 MHz) are correct, but MHz is more commonly used for this frequency range.
Why Other Answers Are Wrong
Option A: Incorrect. 28.400 kHz equals 0.0284 MHz, not 28.400 MHz. You divided by 1,000,000 instead of 1,000. Option B: Incorrect. 2.800 MHz equals 2,800 kHz, not 28,400 kHz. You're off by a factor of 10. Option C: Incorrect. 284.00 MHz equals 284,000 kHz, not 28,400 kHz. You multiplied instead of dividing.
Exam Tip
kHz to MHz = Divide by 1000. Remember: To convert kilohertz to megahertz, divide by 1,000. 28,400 kHz ÷ 1000 = 28.400 MHz.
Memory Aid
**k**Hz **T**o **M**Hz = **D**ivide **T**housand (think 'kTM = DTM' = Divide Thousand, ÷ 1000)
Real-World Example
The 10-meter amateur band includes frequencies around 28.400 MHz, which can also be expressed as 28,400 kHz. Both are correct, but MHz is more commonly used. Understanding that 28,400 kHz = 28.400 MHz helps when working with frequency specifications that might use different units.
Source & Coverage
Question Pool: 2022-2026 Question Pool
Subelement: T5B
Reference: FCC Part 97.303
Key Concepts
Verified Content
Question from the official FCC Technician Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the T5B topic.