radio wave characteristics

Question 1

type of wave that ccarries radio signals between transmitting and receiving stations

Answer 1

electromagnetic

Question 2

unit of frequency

Answer 2

hertz, one cycle per second

Question 3

how fast does a radio wave travel

Answer 3

speed of light

Question 4

wavelength

Answer 4

distance a radio wave travels during one coplete cycle

Question 5

relationship between frequency and wavelength

Answer 5

as frequency increases, wavelength decreases

Question 6

the approximate wavelength

Answer 6

used to identify frequency bands

Question 7

what is RF

Answer 7

radio frequency signals

Question 8

HF vs VHF vs UHF

Answer 8

hf high frequency, 3-30 MHz
vhf very high frequency 30-300
uhf ultrahigh frequency 300-3000

Question 9

why cant you hear uhf signals outside your coverage area

Answer 9

they arent reflected by the ionosphere

Question 10

radio horizon

Answer 10

distance at which radio signals between two points are effectively blocked by the curvature of the earth

Question 11

multi path istortion

Answer 11

random reflections can cause frequencies to become out of phase

Question 12

whats most effective form inside buildings and why

Answer 12

UHF bands, shorter wavelength allows them to penetrate structure of buildings

Question 13

knife edge propagation

Answer 13

signals are partially refracted around solid objects exhibitng shar edges

Question 14

polarization

Answer 14

orientation of electric field

Question 15

vertical vs horizontal antenna polarizationn

Answer 15

horizontal is used for long distance weaek signals

Question 16

picket fencing

Answer 16

rapid fluttering sound sometimes heard form mobile stations that are moving while transmitting

Question 17

how are nhf signals received over long distances

Answer 17

they are refracted from a sporadic e layer

Question 18

what happens to vhf signals bounced off aurora

Answer 18

rapid fluctuations in strength, distortion

Question 19

best band for meteor propagation

Answer 19

6 meters

Question 20

tropospheric scater

Answer 20

responsible for over the horizon vhf uhf ranges, caused by temperature inversionsn

Question 21

HF propagation

Answer 21

enables propagation of radio signnals around the world

Question 22

what meters are best dudring peak of sunspot cycle

Answer 22

6 to 10

Question 23

fading phenomena

Answer 23

random combining of signals arriving via different path lengths, from hf

Question 24

is it important to polarize with hf

Answer 24

no because signas become elliptically polarized from the atmosphere