Key Topic 73: Equipment Functions Flashcards
3-73K1: Some aircraft and avionics equipment operates with a prime power line frequency of 400 Hz. What is the principle advantage of a higher line frequency?
A. 400 Hz power supplies draw less current than 60 Hz supplies allowing more current available for other systems on the aircraft.
B. A 400 Hz power supply generates less head and operates much more efficiently than a 60 Hz power supply.
C. The magnetic devices in a 400 Hz power supply such as transformers, chokes, and filters are smaller and lighter than those used in 60 Hz power supplies.
D. 400 Hz. power supplies are much less expensive to produce than power supplies with lower line frequencies.
C. The magnetic devices in a 400 Hz power supply such as transformers, chokes, and filters are smaller and lighter than those used in 60 Hz power supplies.
3-73K2: Aviation services us predominantly ___ microphones.
A. Dynamic
B. Carbon
C. Condenser
D. Piezoelectric crystal
A. Dynamic
3-73K3: Typical airborne HF transmitters usually provide a nominal RF power output to the antenna of ___ watts, compared with ___ watts RF output from a typical VHF transmitter.
A. 10, 50
B. 50, 10
C. 20, 100
D. 100, 20
D. 100, 20
3-73K4: Before ground testing an aircraft RADAR, the operator should:
A. Ensure that the area in front of the antenna is clear of other maintenance personnel to avoid radiation hazards.
B. Be sure the receiver has been properly shielded and grounded.
C. First test the transmitter connected to a matched load.
D. Measure power supply voltages to prevent circuit damage.
A. Ensure that the area in front of the antenna is clear of other maintenance personnel to avoid radiation hazards.
3-73K5: What type of antenna is used in an aircraft’s Very High Frequency Omnidirectional Range (VOR) and Localizer (LOC) installations?
A. Vertically polarized antenna that radiates an omnidirectional antenna pattern.
B. Horizontally polarized omnidirection reception antenna.
C. Balanced loop transmission antenna.
D. Folded dipole reception antenna.
B. Horizontally polarized omnidirection reception antenna.
3-75K6: What is the function of a commercial aircraft’s SELCAL installation? SELCAL is a type of aircraft communications __________.
A. Device that allows an aircraft’s receiver to be continuously calibrated for signal selectivity.
B. System where a ground-based transmitter can call a selected aircraft or group of aircraft without the flight crew monitoring the ground-station frequency.
C. Transmission that uses sequential logic algorithm encryption to prevent public “eavesdropping” of crucial aircraft flight data.
D. System where an airborne transmitter can selectively calculate the line-of-sight distance to several ground-station receivers.
B. System where a ground-based transmitter can call a selected aircraft or group of aircraft without the flight crew monitoring the ground-station frequency.
