Sub-Element T7 Station equipment: common transmitter and receiver problems, antenna measurements, troubleshooting, basic repair & testing [4 Exam Questions]

Question 1

Which term describes the ability of a receiver to detect the presence of a signal?

Answer 1

Sensitivity

Question 2

What is a transceiver?

Answer 2

A unit combining the functions of a transmitter and a receiver

Question 3

Which of the following is used to convert a radio signal from one frequency to another?

Answer 3

Mixer

Question 4

Which term describes the ability of a receiver to discriminate between multiple signals?

Answer 4

Selectivity

Question 5

What is the name of a circuit that generates a signal at a specific frequency?

Answer 5

Oscillator

Question 6

What device converts the RF input and output of a transceiver to another band?

Answer 6

Transverter

Question 7

What is meant by “PTT”?

Answer 7

The push-to-talk function that switches between receive and transmit

Question 8

Which of the following describes combining speech with an RF carrier signal?

Answer 8

Modulation

Question 9

What is the function of the SSB/CW-FM switch on a VHF power amplifier?

Answer 9

Set the amplifier for proper operation in the selected mode

Question 10

What device increases the low-power output from a handheld transceiver?

Answer 10

An RF power amplifier

Question 11

Where is an RF preamplifier installed?

Answer 11

Between the antenna and receiver

Question 12

What can you do if you are told your FM handheld or mobile transceiver is over-deviating?

Answer 12

Talk farther away from the microphone

Question 13

What would cause a broadcast AM or FM radio to receive an amateur radio transmission unintentionally?

Answer 13

The receiver is unable to reject strong signals outside the AM or FM band

Question 14

Which of the following can cause radio frequency interference?

Answer 14

All of these choices are correct

Question 15

Which of the following is a way to reduce or eliminate interference from an amateur transmitter to a nearby telephone?

Answer 15

Put an RF filter on the telephone

Question 16

How can overload of a non-amateur radio or TV receiver by an amateur signal be reduced or eliminated?

Answer 16

Block the amateur signal with a filter at the antenna input of the affected receiver

Question 17

Which of the following actions should you take if a neighbor tells you that your station’s transmissions are interfering with their radio or TV reception?

Answer 17

Make sure that your station is functioning properly and that it does not cause interference to your own radio or television when it is tuned to the same channel

Question 18

Which of the following can reduce overload to a VHF transceiver from a nearby FM broadcast station?

Answer 18

Band-reject filter

Question 19

What should you do if something in a neighbor’s home is causing harmful interference to your amateur station?

Answer 19

All of these choices are correct

Question 20

What is a Part 15 device?

Answer 20

An unlicensed device that may emit low-powered radio signals on frequencies used by a licensed service

Question 21

What might be a problem if you receive a report that your audio signal through the repeater is distorted or unintelligible?

Answer 21

All of these choices are correct

Question 22

What is a symptom of RF feedback in a transmitter or transceiver?

Answer 22

Reports of garbled, distorted, or unintelligible voice transmissions

Question 23

What should be the first step to resolve cable TV interference from your ham radio transmission?

Answer 23

Be sure all TV coaxial connectors are installed properly

Question 24

What is the primary purpose of a dummy load?

Answer 24

To prevent transmitting signals over the air when making tests

Question 25

Which of the following instruments can be used to determine if an antenna is resonant at the desired operating frequency?

Answer 25

An antenna analyzer

Question 26

What, in general terms, is standing wave ratio (SWR)?

Answer 26

A measure of how well a load is matched to a transmission line

Question 27

What reading on an SWR meter indicates a perfect impedance match between the antenna and the feed line?

Answer 27

1 to 1

Question 28

Why do most solid-state amateur radio transmitters reduce output power as SWR increases?

Answer 28

To protect the output amplifier transistors

Question 29

What does an SWR reading of 4:1 indicate?

Answer 29

Impedance mismatch

Question 30

What happens to power lost in a feed line?

Answer 30

It is converted into heat

Question 31

What instrument other than an SWR meter could you use to determine if a feed line and antenna are properly matched?

Answer 31

Directional wattmeter

Question 32

Which of the following is the most common cause for failure of coaxial cables?

Answer 32

Moisture contamination

Question 33

Why should the outer jacket of coaxial cable be resistant to ultraviolet light?

Answer 33

Ultraviolet light can damage the jacket and allow water to enter the cable

Question 34

What is a disadvantage of air core coaxial cable when compared to foam or solid dielectric types?

Answer 34

It requires special techniques to prevent water absorption

Question 35

What does a dummy load consist of?

Answer 35

A non-inductive resistor and a heat sink

Question 36

Which instrument would you use to measure electric potential or electromotive force?

Answer 36

A voltmeter

Question 37

What is the correct way to connect a voltmeter to a circuit?

Answer 37

In parallel with the circuit

Question 38

How is a simple ammeter connected to a circuit?

Answer 38

In series with the circuit

Question 39

Which instrument is used to measure electric current?

Answer 39

An ammeter

Question 40

What instrument is used to measure resistance?

Answer 40

An ohmmeter

Question 41

Which of the following might damage a multimeter?

Answer 41

Attempting to measure voltage when using the resistance setting

Question 42

Which of the following measurements are commonly made using a multimeter?

Answer 42

Voltage and resistance

Question 43

Which of the following types of solder is best for radio and electronic use?

Answer 43

Rosin-core solder

Question 44

What is the characteristic appearance of a cold solder joint?

Answer 44

A grainy or dull surface

Question 45

What is probably happening when an ohmmeter, connected across an unpowered circuit, initially indicates a low resistance and then shows increasing resistance with time?

Answer 45

The circuit contains a large capacitor

Question 46

Which of the following precautions should be taken when measuring circuit resistance with an ohmmeter?

Answer 46

Ensure that the circuit is not powered

Question 47

Which of the following precautions should be taken when measuring high voltages with a voltmeter?

Answer 47

Ensure that the voltmeter and leads are rated for use at the voltages to be measured