May 24, 2014

FCC Technician Exam Question Of The Day (T9A08)

Q) What is the approximate length, in inches, of a quarter-wavelength vertical antenna for 146 MHz?

A) 19

NJ2X Notes:
Electromagnetic waves travel at the speed of light which is 299,792,458 meters per second or for the ease of calculation we can round up to 300,000,000 m/s.  Frequency and wavelength are related and can be determined by the formulas:

Frequency = Speed of Light / Wavelength


Wavelength = Speed of Light / Frequency

The easiest way to deal with this question is to simply memorize the answer