3.5 KiB
3.5 KiB
G4E – Mobile and portable HF stations; alternative energy source operation
- G4E01 (C)
What is the purpose of a capacitance hat on a mobile antenna? #card
- A. To increase the power handling capacity of a whip antenna
- B. To reduce radiation resistance
- C. To electrically lengthen a physically short antenna
- D. To lower the radiation angle
- G4E02 (D)
What is the purpose of a corona ball on an HF mobile antenna? #card
- A. To narrow the operating bandwidth of the antenna
- B. To increase the “Q” of the antenna
- C. To reduce the chance of damage if the antenna should strike an object
- D. To reduce RF voltage discharge from the tip of the antenna while transmitting
- G4E03 (A)
Which of the following direct, fused power connections would be the best for a 100-watt HF mobile installation? #card
- A. To the battery using heavy-gauge wire
- B. To the alternator or generator using heavy-gauge wire
- C. To the battery using insulated heavy duty balanced transmission line
- D. To the alternator or generator using insulated heavy duty balanced transmission line
- G4E04 (B)
Why should DC power for a 100-watt HF transceiver not be supplied by a vehicle’s auxiliary power socket? #card
- A. The socket is not wired with an RF-shielded power cable
- B. The socket’s wiring may be inadequate for the current drawn by the transceiver
- C. The DC polarity of the socket is reversed from the polarity of modern HF transceivers
- D. Drawing more than 50 watts from this socket could cause the engine to overheat
- G4E05 (C)
Which of the following most limits an HF mobile installation? #card
- A. “Picket fencing”
- B. The wire gauge of the DC power line to the transceiver
- C. Efficiency of the electrically short antenna
- D. FCC rules limiting mobile output power on the 75-meter band
- G4E06 (C)
What is one disadvantage of using a shortened mobile antenna as opposed to a full-size antenna? #card
- A. Short antennas are more likely to cause distortion of transmitted signals
- B. Q of the antenna will be very low
- C. Operating bandwidth may be very limited
- D. Harmonic radiation may increase
- G4E07 (D)
Which of the following may cause receive interference to an HF transceiver installed in a vehicle? #card
- A. The battery charging system
- B. The fuel delivery system
- C. The control computers
- D. All these choices are correct
- G4E08 (A)
In what configuration are the individual cells in a solar panel connected together? #card
- A. Series-parallel
- B. Shunt
- C. Bypass
- D. Full-wave bridge
- G4E09 (B)
What is the approximate open-circuit voltage from a fully illuminated silicon photovoltaic cell? #card
- A. 0.02 VDC
- B. 0.5 VDC
- C. 0.2 VDC
- D. 1.38 VDC
- G4E10 (B)
Why should a series diode be connected between a solar panel and a storage battery that is being charged by the panel? #card
- A. To prevent overload by regulating the charging voltage
- B. To prevent discharge of the battery through the panel during times of low or no illumination
- C. To limit the current flowing from the panel to a safe value
- D. To prevent damage to the battery due to excessive voltage at high illumination levels
- G4E11 (D)
What precaution should be taken when connecting a solar panel to a lithium iron phosphate battery? #card
- A. Ground the solar panel outer metal framework
- B. Ensure the battery is placed terminals-up
- C. A series resistor must be in place
- D. The solar panel must have a charge controller