Electronics and Communications Flashcards
The depletion region of a junction diode forms the ____________ of the capacitor.
A. Plates
B. Dielectric
C. Package
D. none of these
Dielectric
Which of the following defined the Fermi energy?
A. The amount of energy which a valence electron can have at room temperature.
B. The amount of energy which a hole can have at room temperature.
C. The amount of energy which must be given to an electron to move it to conductor band.
D. The amount of energy which must be given to hole it in valence band.
The amount of energy which must be given to an electron to move it to conductor band.
What is the equivalent of the collector terminal of transistor in FET?
A. grid
B. gate
C. source
D. drain
Drain
In which type of electronic communication does the information travel in two directions?
A. half duplex
B. full duplex
C. multiplex
D. bicomm
full duplex
A type of electronics communication in which only one party transmits at a time.
A. Full duplex
B. Half duplex
C. Bicom
D. Simplex
Half duplex
Amplitude modulation generated at a very low voltage or power amplifier is _______ modulation.
A. Minimum
B. Collector
C. high-level
D. low-level
low-level
Which of the following is a primary disadvantage of FM over AM?
A. Lower efficiency
B. Noise susceptibility
C. Higher cost and complexity
D. Excessive use of spectrum space
Excessive use of spectrum space
The amount of frequency deviation from the carrier center of frequency in an FM transmitter is proportional to the ________.
A. shape
B. amplitude
C. frequency
D. phase
amplitude
A type of communication that uses light rather than electricity to communicate is called
A. Laser carrier
B. Microwave
C. Powerline carrier
D. Fiber optic
Fiber optic
Which of the following principle will the operation of fiber-optic cable is based?
A. dispersion
B. refraction
C. reflection
D. absorption
reflection
Which of the following carries the most number of channels?
A. 50 multiplexer
B. 100 cable pairs
C. 100 chips
D. 1 fiber optic
1 fiber optic
What is the optical source for the transmitting end of an optic fiber cable?
A. halogen
B. LED
C. Injection Laser Diode
D. Photocell
LED
What is the most commonly used fiber optic cable?
A. single mode step index
B. single mode graded index
C. Multi mode step index
D. Multi mode graded index
Multi mode step index
What replaces coaxial cable for terrestrial transmission?
A. copper cable
B. point to point wireless transmission
C. aluminum cable
D. fiber optics
point to point wireless transmission
What is the common unit of the sound absorption coefficient?
A. Watt
B. erg
C. sabine
D. decibel
sabine
What contains in each cell site of cellular telephone system?
A. Repeater
B. touch tone processor
C. direct-link to branch
D. control computer
Repeater
It refers to a device that merely boosts a signal and passes it on.
A. Amplifier
B. booster
C. op-amp
D. repeater
repeater
The master control center for a cellular telephone system is the
A. cell site
B. mobile telephone switching office
C. Central Office
D. Branch office
mobile telephone switching office
What is the maximum output power of a cellular transmitter?
A. 60 watts
B. 3 watts
C. 6 watts
D. 30 watts
3 watts
An ideal full wave rectifier with a non-inductive load has zero transformation losses. What is the efficiency?
A. 100
B. 90
C. 80
D. 70
80
