AJX Radio engineering Exam Review Flashcards
What is SSR mode A?
The basic mode that is capable of discriminating an aircraft Identification code
What determines the azimuth of a target?
The direction of the antenna
Amplitude modulation causes generation of what?
Side bands
Fill in the blanks:
To hear the ________, partial power of the ______ system is fed back to the _______ system through a detector to provide ______.
To hear the –voice being transmitted–, partial power of the –transmitting– system is fed back to the –receiving– system through a detector to provide –side tone–.
Why does SSB system use one side band only?
Because either one side band contains all message information
HF communication quality is deteriorated by what depending on the strength of the sun’s activity?
By magnetic storm or the Dellinger phenomenon
Fill in the blanks:
When receiving signal is strong the voltage of the ____________is ___________and the receiver gain is ____________for preventing of ____________
When receiving signal is strong, the voltage of the –automatic gain control– is –high– and the receiver gain is –reduced– for preventing –overloading–
A carrier wave is generated by what?
An oscillator
Fill in the blanks:
The transmitter generates _________. The message signal________ the current. The modulated high-frequency current is fed to the_________.
The transmitter generates –high frequency electric current–. The message signal –modulates– the current. The modulated high-frequency current is fed to the –antenna–.
Fill in the blanks:
In weak receiving conditions, the ACG voltage is __________to ________ the receiver gain
In weak receiving conditions, the AGC voltage is low to increase to receiver gain
Radio equipment requires what type of power?
DC power
What sort of antennas are applied to VHF and UHF range equipment?
Sleeve antenna, Brown antenna and Yagi antenna
In the ionosphere which layer reflects HF radio waves
The F layer
The side tone is what?
A feedback of the transmitting signal to the receiving system
How is radar distance calculated?
From the elapsed time of the radio signal spent for the round trip between the antenna and the target
The Yagi antenna is what type of antenna
A directional antenna
How is the AC of the engine driven generator changed to DC?
With the Transformer rectifier unit (TRU)
Fill in the blanks:
The carrier wave is _______ by the ______ and the _________ is amplified to a sufficient level for _________.
The carrier wave is –modulated– by the –signal wave– and the –modulated carrier wave – is amplified to a sufficient level for –transmission–.
What is SSR mode C?
Mode C has an additional capability of automatic altitude reporting over the mode A system.
What is SSR mode S?
Mode S is capable of automatic addressing of an individual aircraft and data link between aircraft and SSR stations
