Wireless Systems

Question 1

In order to receive a radio transmission, the antenna that you’re using has to be at least a _____ wave of the signal you’re trying to receive

Answer 1

quarter (1/4)

Question 2

The first gain stage in wireless is always in the

Answer 2

transmitter

Question 3

Radio waves travel at

Answer 3

a fixed speed

Question 4

radio waves do not require a __________ in order to propagate

Answer 4

a physical medium (air, water, etc.)

Question 5

Radio waves and sound waves can be expressed in _______ and ________.

Answer 5

amplitude, frequency

Question 6

There’s a ______ in the Beltpack Wireless Transmitter which has _____ setting

Answer 6

Mic Pre, One

Question 7

AM =

Answer 7

Amplitude Modulation

Question 8

FM =

Answer 8

Frequency Modulation

Question 9

Antenna =

Answer 9

An electrical circuit element that transmits or receives radio waves

Question 10

Band =

Answer 10

a defined portion of the frequency spectrum

Question 11

Commander =

Answer 11

a two-step noise reduction system consisting of a compressor in the transmitter and an expander in the receiver.

Question 12

De-emphasis =

Answer 12

a fixed equalization which typically rolls of high frequencies in the second step of a two-step noise reduction system.

Question 13

Deviation =

Answer 13

the maximum frequency variation allowed (by both physics and regulation) as a result of the varying amplitude of the modulating audio signal.

Question 14

Diffraction =

Answer 14

the bending or partial reflection of radio waves by metal objects

Question 15

Dipole =

Answer 15

an antenna which is made up of two active elements

Question 16

Diversity =

Answer 16

a receiver design which picks up a radio signal simultaneously at multiple locations and intelligently switches or combines to yield the best continuous signal.

Question 17

Dropout =

Answer 17

the complete loss of received signal due to multi-path interference.

Question 18

Frequency Agile =

Answer 18

having the ability to change frequencies ; tunable. devices that are frequency agile include: cell phones, CB radios, scanners, TV’s, radios, etc.

Question 19

C / FC….. where C = ___________ miles per second and F =____________

Answer 19

186,000, Frequency of the carrier

Question 20

Ground Plane =

Answer 20

an electrical approximation of a zero-potential reflective surface at the base of an antenna

Question 21

IM =

Answer 21

a negative side effect of using two transmitters whose frequencies are mathematically related to one another

Question 22

Modulation =

Answer 22

the variation of a wave parameter (such as amplitude or frequency) in that it may “carry” information.

Question 23

Receiver =

Answer 23

a device which is sensitive to radio signals and recovers information from them.

Question 24

RF =

Answer 24

radio frequency. Generally taken to mean frequencies will above 20kHz

Question 25

RFI =

Answer 25

radio frequency interference

Question 26

Squelch =

Answer 26

a circuit in a receiver that mutes the audio output in the absence of the desired transmitter signal. This Is essentially a threshold control for a white-noise gate. adjusting the threshold above the white-noise will mute the output of the receiver, when there is no radio signal present.

Question 27

Transmitter =

Answer 27

a device which converts information to radio signal.