WorksheetsIntroduction to Electronic Communication
Total questions: 18
Worksheet time: 26mins
Having an information signal change some characteristic of a carrier signal is called
Multiplexing
Modulation
Duplexing
Linear mixing
Which of the following is not true about AM?
the carrier amplitude varies
the carrier frequency remains constant
the carrier frequency changes
the information signal amplitude changes the carrier amplitude
The opposite of modulation is
reverse modulation
downward modulation
unmodulation
demodulation
What is the process of superimposing an intelligence frequency to a higher frequency?
Modulation
Detection
Multiplexing
Scrambling
When the carrier is modulated 75%, the total power increases by what percentage over that of the carrier alone?
50%
75%
28%
100%
The ratio of the peak modulating signal voltage to the peak carrier voltage is referred to as
modulation ratio
percentage of modulation
modulation index
coefficient of modulation
For ideal AM, which of the following is true?
m = 0
m = 1
m < 1
m > 1
The outline of the peaks of a carrier has the shape of the modulating signal and is called the
trace
waveshape
envelope
carrier variation
Overmodulation occurs when
Vm > Vc
Vm < Vc
Vm = Vc
Vm = Vc = 0
Most of the power in an AM signal is the
carrier
upper sideband
lower sideband
modulating signal
A carrier of 880 kHz is modulated by a 3.5 kHz sine wave. The LSB is ______ kHz.
A sine wave carrier is modulated by a single tone so the Vmax = 18mV and Vmin = 10mV. Calculate the modulation index.
If a 7-ampere carrier is modulated 100% by a sinusoidal tome, how much does the antenna current increase? In percent.
An AM signal has a carrier power of 5 W. The percentage of modulation is 80 percent. The total sideband power is
An AM transmitter has a percentage of modulation of 88. The carrier power is 440 W. The power in one sideband is
300 kHz
3 MHz
3000 MHz
0.3 MHz
25 MHz
1.56 GHz
Discuss and differentiate under modulation and over modulation
Discuss the process of Amplitude Modulation including the relationship of its parameters (index, power, voltage/amplitude).
