1. TECHNICIAN BANDS RADIO AND SIGNAL FUNDAMENTALS
CHPT 2, THE ARRL HAM RADIO LICENSE MANUAL

2. Understanding Radio Waves
To understand BANDS you first must understand what FREQUENCIES are.
Why? Bands are Frequency divisions.
To understand FREQUENCIES you must have an understanding of RADIO WAVES.

3. Understanding Radio Waves
Signals that travel back and forth between radios, carrying voices, data, and morse code.
These radio waves travel at the speed of light (300,000,000 m/s). A radio wave begins its journey as an electrical signal in an antenna that constantly alternates direction. The rate at which the signal changes direction determines the signal’s frequency. The radio wave then travels away from the antenna into space, vibrating or oscillating at the same frequency as the electrical signal.
These radio waves are also known as:
ELECTROMAGNETIC WAVES
Understanding Radio Waves

4. RADIO OR ELECTROMAGNETIC WAVES
What are electromagnetic waves?
Electromagnetic waves or EM waves are waves that are created as a result of vibrations between an electric field and a magnetic field. In other words, EM waves are composed of oscillating magnetic and electric fields.

5. The Electric Field is perpendicular to the Magnetic Field (and visa-versa). These are perpendicular to the Wave Direction of travel.

6. Wavelength is the physical length from one point of a wave to the same point on the next wave.
Usually measured in Meters

7. Decimal Equivalencies
Prefix
Symbol
Multiplication Factor
Tera T
= 1,000,000,000,000
Giga G
= 1,000,000,000
Mega M
= 1,000,000
Kilo k
= 1,000
Hecto h
= 100
Deca da
= 10
Deci d
= 0.1
Centi c
= 0.01
Milli m =
Micro μ =
Nano n =
Pico p =

8. Formula for Wavelength
(in Hz)

9. Example Wavelength Calculations
(300,000,000 m/s)
(in Hz)
300,000,000
300,000,000 meters
Wavelength = =
= meters
MHz
145,440,000 Hz
300,000,000
Wavelength =
= meters = cm
MHz
300,000,000
= meters
Wavelength =
1.8 MHz

10. UNIT OF MEASUREMENT: HERTZ
The unit of measurement for frequency is called the Hertz, abbreviated as Hz.
One cycle per second is one hertz or 1 Hz. 60 cycles per second is 60 Hz.

11. FREQUENCY
As the signal oscillates, each complete back-and-forth sequence is called a cycle.
The number of cycles per second is the signals’ FREQUENCY.

12. The number of cycles / second = Frequency

13. AMPLITUDE The Amplitude is the height of the wave.
Often this is related to Power.

14. AMPLITUDE
The Amplitude is the height of the wave, and is often related to Power.

15. PHASE
Phase is not a property of just one RF signal, but instead involves the relationship between two or more signals that share the same frequency. The phase involves the relationship between the position of the amplitude crests and troughs of two waveforms.
Phase can be measured in distance, time, or degrees. If the peaks of two signals with the same frequency are in exact alignment at the same time, they are said to be in phase. Conversely, if the peaks of two signals with the same frequency are not in exact alignment at the same time, they are said to be out of phase.

16. The above graph shows two waves that are 90° out of phase

17. THE BAND PLAN
RF SPECTRUM RANGES

18. RF Spectrum Ranges RANGE NAME ABREVIATION FREQUENCY RANGE
Very Low Frequency
VLF
3 kHz – 30 kHz
Low Frequency LF
30 kHz – 300 kHz
Medium Frequency MF
300 kHz – 3 MHz
High Frequency HF
3 MHz – 30 MHz
Very High Frequency
VHF
30 MHz – 300 MHz
Ultra High Frequency
UHF
300 MHz – 3 GHz
Super High Frequency
SHF
3 GHz – 30 GHz
Extremely High Frequency
EHF
30 GHz – 300 GHz

19. Radio Frequency Spectrum

21. US AMATEUR RADIO TECHNICIAN PRIVILEGES (Band plan for all Technicians)

22. US AMATEUR RADIO TECHNICIAN PRIVILEGES UHF

23. US AMATEUR RADIO TECHNICIAN PRIVILEGES VHF

24. US AMATEUR RADIO TECHNICIAN PRIVILEGES HF

25. Popular ARRL Band Plan Diagram