7.4 Avionic Test Equipment Flashcards
What is the purpose of avionics general test equipment?
To measure and verify the function of avionics systems and components
Includes equipment like power meters, frequency counters, oscilloscopes, and pitot/static system test sets.
How is power in an electric circuit calculated?
Power is the product of voltage and current
This means Power (P) = Voltage (V) x Current (I).
What is the function of a dynamometer movement in power measurement?
Measures power by utilizing a moving coil and stationary coil to react to voltage and current
The moving coil reacts to voltage, while the stationary coil reacts to current.
What is a wattmeter used for?
To measure electrical power in a circuit
Rated in volts and amperes, not in watts.
What is the significance of frequency in AC circuits?
Frequency is crucial for the efficiency of AC power systems
AC circuits operate optimally at a specific frequency.
What components are typically used in a resonant frequency meter?
Inductor and capacitor in a tank circuit
The components may be adjustable to determine resonant frequency.
How does a frequency counter determine frequency?
By counting pulses during a specific time interval
The number of pulses counted is divided by the time the gate is open.
What is a direct digital counter?
A type of frequency counter that uses digital counting techniques
It is accurate and user-friendly for frequency measurement.
What is the primary function of an oscilloscope?
To display time-related voltage waveforms
It can also be used for frequency and voltage measurement.
What role do the grids G1, G2, and G3 play in a cathode ray tube (CRT)?
They control the electron gun and the display of the luminous spot on the screen
G1 controls the brightness, while G2 and G3 accelerate and focus the electrons.
What is the time base in an oscilloscope?
A circuit that supplies a voltage varying linearly with time to the horizontal deflecting plates
It ensures that the signal waveform is displayed as a function of time.
What is the function of a pitot/static system in aircraft?
To provide static and dynamic air pressure to flight instruments
Instruments include altimeters and airspeed indicators.
What are the two types of tests performed with pitot/static testers?
- Operating sense check
- Leak test
The leak test ensures the system is not losing pressure.
What is the purpose of a low-range leak check?
To verify system integrity after disconnection of pitot or static lines
A full range leak check is done if any leaks are suspected.
What does an air data test set do?
Carries out high-range leak checks and calibration of air-data instruments
It also tests ATC transponder MODE C altitude reporting.
Fill in the blank: The horizontal coil in a dynamometer movement measures _______.
load-current
Fill in the blank: A frequency counter typically consists of an accurate clock signal source, a gate circuit, and a _______.
digital counter
True or False: An oscilloscope can only measure voltage.
False
It can also measure frequency.
What happens during the fly back time in an oscilloscope?
The spot returns rapidly to the left of the screen
This is to start a new cycle of the display.
