T1 · Published 17 August 2026 · By The Ham Desk

Frequency, Wavelength and the Bands You Will Actually Use

Every amateur band is named after a wavelength, but every dial and every licence privilege is written in frequency. This unit drills the one conversion that ties them together, the metric prefixes that appear on every radio display, and the band edges a Technician certificate actually opens.

Band 2 m
Study time 14
Level Recall
questions 10

Waveform and antenna diagram for Radio and Signals Fundamentals — Radio and Signals Fundamentals — waveform overlay and radiation pattern

Pre-flight briefing

The 300 rule

Wavelength in metres is 300 divided by frequency in megahertz. The 300 is the speed of light rounded to 300 million metres per second, so the arithmetic works with two significant figures: 146 MHz gives 2.05 m, which is why the band is called 2 metres; 28.4 MHz gives 10.56 m, hence 10 metres; 50 MHz gives 6 m exactly.

Read the rule backwards as well. If someone says the antenna is cut for a quarter wave on 40 m, and you need the frequency, 300 divided by 40 m gives 7.5 MHz - the middle of the 40 metre band.

HF, VHF and UHF are just ranges

High frequency means 3 to 30 MHz, very high frequency means 30 to 300 MHz, and ultra high frequency means 300 MHz to 3 GHz. So 10 m (28 to 29.7 MHz) is HF, 6 m (50 to 54 MHz) and 2 m (144 to 148 MHz) are VHF, and 70 cm (420 to 450 MHz) and 23 cm (1240 to 1300 MHz) are UHF. A Technician licence is mostly a VHF/UHF licence, with narrow data and CW slices of 10 m, 15 m, 40 m and 80 m.

Prefixes that trip people up

One kilohertz is a thousand hertz, one megahertz is a thousand kilohertz, and one gigahertz is a thousand megahertz. A repeater listed at 146.940 MHz is also 146,940 kHz, and a 23 cm station at 1,296,000 kHz is 1296 MHz or 1.296 GHz. Exam questions often hand you one form and ask for another, so convert first and only then decide what the question is really about.

Terms you must be able to define
Term	What the examiner wants to hear
Wavelength	The distance between two consecutive peaks of a wave; in metres it is 300 divided by frequency in MHz.
HF / VHF / UHF	3-30 MHz, 30-300 MHz and 300-3000 MHz respectively; the boundaries are decade steps, not band edges.
kHz, MHz, GHz	Thousand, million and billion hertz; each step is a factor of one thousand.
Band name	A nickname taken from the approximate wavelength, so 2 m means the 144-148 MHz allocation.

Question deck 10 questions

T1A01 Recall

What is the approximate wavelength of a 146 MHz signal?

T1A02 Recall

In the expression wavelength = 300 / frequency, what does 300 stand for?

T1A03 Recall

Which amateur band corresponds to a wavelength of approximately 70 centimetres?

T1A04 Recall

Which frequency range is described as high frequency (HF)?

T1A05 Core

A Technician holds full privileges on 6 metres. Which band is that, and is it VHF or UHF?

T1A06 Core

How many megahertz is 1,296,000 kHz?

T1A07 Recall

What are the frequency limits of the 2 metre amateur band in the United States?

T1A08 Core

Why is the 10 metre band so called, and where does it sit in the spectrum?

T1A09 Stretch

A repeater transmits on 442.150 MHz. Roughly how long is one complete cycle of that signal?

T1A10 Stretch

Which of these statements about band names is correct?

Reference sheet

The explanations for all ten questions sit on this sheet. Pick an answer on the left and the matching card lights up.

T1A01 Explanation 1

Key B — 2.05 metres

Wavelength in metres is 300 divided by frequency in megahertz: 300 / 146 = 2.05 m. That is why the 144-148 MHz allocation is called the 2 metre band.

Rule 47 CFR §97.301(a) - 144-148 MHz is allocated to the amateur service

T1A02 Explanation 2

Key A — The speed of light rounded to 300 million metres per second

The speed of light is about 300,000,000 metres per second; dividing it by a frequency in megahertz (millions of cycles per second) leaves metres per cycle, which is the wavelength. The same relationship gives 468/f for a half-wave dipole in feet, where the 468 packs in the conversion to feet and the end effect.

Rule Fundamentals - no rule citation; the arithmetic follows from the definition of frequency

T1A03 Explanation 3

Key D — 420-450 MHz

300 / 440 MHz = 0.68 m, close enough to 70 cm. The 144-148 MHz allocation is 2 m, 1240-1300 MHz is 23 cm, and 50-54 MHz is 6 m.

Rule 47 CFR §97.301(a) / (b) - 420-450 MHz UHF allocation

T1A04 Explanation 4

Key C — 3 to 30 MHz

HF covers 3-30 MHz. 30-300 MHz is VHF, 300 MHz to 3 GHz is UHF, and 300 kHz to 3 MHz sits in the medium frequency range.

Rule 47 CFR §97.301 - frequency bands by class

T1A05 Explanation 5

Key B — 50-54 MHz, VHF

The 6 metre band is 50-54 MHz, which falls inside the 30-300 MHz VHF range. The 222-225 MHz allocation is the 1.25 metre band, not 6 metres.

Rule 47 CFR §97.301(a) - 50-54 MHz is a Technician allocation

T1A06 Explanation 6

Key A — 1296 MHz

Divide kilohertz by 1000 to get megahertz: 1,296,000 / 1000 = 1296 MHz, which is also 1.296 GHz and sits in the 23 centimetre band.

Rule 47 CFR §97.301(b) - 1240-1300 MHz amateur allocation

T1A07 Explanation 7

Key D — 144.0 to 148.0 MHz

The amateur allocation is 144-148 MHz, a full 4 MHz of spectrum that carries the national simplex calling frequency at 146.520 MHz and most of the 2 metre FM repeaters.

Rule 47 CFR §97.301(a) - 144-148 MHz

T1A08 Explanation 8

Key C — Wavelength is about 10 m at 28-29.7 MHz, in the HF range

300 / 28.4 MHz = 10.56 m, so the band takes its name from the wavelength, and 28-29.7 MHz sits inside the 3-30 MHz HF range. Technicians may use CW and data in the 28.0-28.5 MHz segment and phone from 28.3 to 28.5 MHz.

Rule 47 CFR §97.301(e) - Technician 10 metre segments

T1A09 Explanation 9

Key B — 0.68 metres

300 / 442.15 = 0.68 m, the wavelength that gives the 70 centimetre band its name. The alternatives correspond to 200 MHz (1.5 m), 133 MHz (2.26 m) and 44 MHz (6.8 m).

Rule Fundamentals - wavelength arithmetic

T1A10 Explanation 10

Key B — A band name is a rounded wavelength, so the band edges are not exactly that wavelength

The names are conveniences: 2 metres covers 144-148 MHz, a wavelength spread of 2.08 m down to 2.03 m. Nothing about the name constrains the antenna you choose, and the names come from decades of usage rather than from an ITU schedule.

Rule Fundamentals - band naming convention

How to use this unit

Work the ten questions in one sitting with the reference sheet covered, then uncover it and read every explanation - including the ones you got right. The wording of the real exam is different, so learn the reasoning rather than the answer letters.