G4C: Interference with consumer electronics; grounding
G4C01:
Which of the following might be useful in reducing RF interference to audio-frequency devices?
Bypass capacitor
Bypass inductor
Forward-biased diode
Reverse-biased diode
G4C02:
Which of the following should be installed if a properly operating amateur station is interfering with a nearby telephone?
An RFI filter at the affected telephone
An RFI filter on the transmitter
A high pass filter on the transmitter
A high pass filter at the affected telephone
G4C03:
What sound is heard from a public-address system if there is interference from a nearby single-sideband phone transmitter?
Distorted speech
A steady hum whenever the transmitter is on the air
On-and-off humming or clicking
Clearly audible speech
G4C04:
What is the effect on a public-address system if there is interference from nearby CW transmitter?
On-and-off humming or clicking
A CW signal at a nearly pure audio frequency
A chirpy CW signal
Severely distorted audio
G4C05:
What might be the problem if you receive an RF burn when touching your equipment while transmitting on a HF band, assuming the equipment is connected to a ground rod?
The ground wire is resonant
Flat braid rather than round wire has been used for the ground wire
Insulated wire has been used for the ground wire
The ground rod is resonant
G4C06:
Which of the following is an important reason to have a good station ground?
All of these answers are correct
To reduce the likelihood of RF burns
To reduce the likelihood of electrical shock
To reduce interference
G4C07:
What is one good way to avoid stray RF energy in an amateur station?
Keep the station's ground wire as short as possible
Install an RF filter in series with the ground wire
Use a ground loop for best conductivity
Install a few ferrite beads on the ground wire where it connects to your station
G4C08:
Which of the following is a reason to place ferrite beads around audio cables to reduce common mode RF interference?
They act as a series inductor
They act as a shunt capacitor
They lower the impedance of the cable
They increase the admittance of the cable
G4C09:
Which of the following statements about station grounding is true?
RF hot spots can occur in a station located above the ground floor if the equipment is grounded by a long ground wire
The chassis of each piece of station equipment should be tied together with high-impedance conductors
If the chassis of all station equipment is connected with a good conductor, there is no need to tie them to an earth ground
A ground loop is an effective way to ground station equipment
G4C10:
Which of the following is covered in the National Electrical Code?
Electrical safety inside the ham shack
Acceptable bandwidth limits
Acceptable modulation limits
RF exposure limits of the human body
G4C11:
Which of the following can cause unintended rectification of RF signal energy and can result in interference to your station as well as nearby radio and TV receivers?
Induced currents in conductors that are in poor electrical contact
Induced voltages in conductors that are in good electrical contact
Capacitive coupling of the RF signal to ground
Excessive standing wave ratio (SWR) of the transmission line system
G4C12:
What is one cause of broadband radio frequency interference at an amateur radio station?
Arcing at a poor electrical connection
Not using a balun or line isolator to feed balanced antennas
Lack of rectification of the transmitter's signal in power conductors
The use of horizontal, rather than vertical antennas
G4C13:
How can a ground loop be avoided?
Connect all ground conductors to a single point
Series connect all ground conductors
Connect the AC neutral conductor to the ground wire
Avoid using lock washers and star washers in making ground connections
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