Chapter 7-3: Coax & Connectors

Which of the following is a reason to use shielded wire?

• To decrease the resistance of DC power connections

• To increase the current carrying capability of the wire

• To prevent coupling of unwanted signals to or from the wire

• To couple the wire to other signals

What is a benefit of low SWR?

• Reduced television interference

• Reduced signal loss

• Less antenna wear

• All these choices are correct

Tags

NGSS.HS-PS4-5

Why is coaxial cable the most common feed line for amateur radio antenna systems?

• It is easy to use and requires few special installation considerations

• It has less loss than any other type of feed line

• It can handle more power than any other type of feed line

• It is less expensive than any other type of feed line

Tags

NGSS.HS-PS4-5

What happens to power lost in a feed line?

• It increases the SWR

• It is radiated as harmonics

• It is converted into heat

• It distorts the signal

Tags

NGSS.HS-PS4-5

Which of the following causes failure of coaxial cables?

• Moisture contamination

• Solder flux contamination

• Rapid fluctuation in transmitter output power

• Operation at 100% duty cycle for an extended period

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

• Ultraviolet resistant jackets prevent harmonic radiation

• Ultraviolet light can increase losses in the cable’s jacket

• Ultraviolet and RF signals can mix, causing interference

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

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

• It has more loss per foot

• It cannot be used for VHF or UHF antennas

• It requires special techniques to prevent moisture in the cable

• It cannot be used at below freezing temperatures

What happens as the frequency of a signal in coaxial cable is increased?

• The characteristic impedance decreases

• The loss decreases

• The characteristic impedance increases

• The loss increases

Tags

NGSS.HS-PS4-5

Which of the following is true of PL-259 type coax connectors?

• They are preferred for microwave operation

• They are commonly used at HF and VHF frequencies

• They are a bayonet-type connector

Which of the following is a source of loss in coaxial feed line?

• Water intrusion into coaxial connectors

• High SWR

• Multiple connectors in the line

• All these choices are correct