2015-G8A: Carriers and modulation: AM; FM; single sideband; modulation envelope; digital modulation; overmodulation
How is an FSK signal generated?
By changing an oscillator’s frequency directly with a digital control signal
By keying an FM transmitter with a sub-audible tone
By using a transceiver’s computer data interface protocol to change frequencies
By reconfiguring the CW keying input to act as a tone generator
What is the name of the process that changes the phase angle of an RF wave to convey information?
What is the name of the process that changes the instantaneous frequency of an RF wave to convey information?
What emission is produced by a reactance modulator connected to a transmitter RF amplifier stage?
What type of modulation varies the instantaneous power level of the RF signal?
Frequency shift keying
What is one advantage of carrier suppression in a single sideband phone transmission versus full carrier amplitude modulation?
Available transmitter power can be used more effectively
Audio fidelity is improved
Greater modulation percentage is obtainable with lower distortion
Simpler receiving equipment can be used
Which of the following phone emissions uses the narrowest bandwidth?
Which of the following is an effect of overmodulation?
What control is typically adjusted for proper ALC setting on an amateur single sideband transceiver?
Transmit audio or microphone gain
The RF clipping level
Antenna inductance or capacitance
What is meant by the term flat-topping when referring to a single sideband phone transmission?
Signal distortion caused by excessive drive
Signal distortion caused by insufficient collector current
The transmitter's automatic level control (ALC) is properly adjusted
The transmitter's carrier is properly suppressed
What is the modulation envelope of an AM signal?
The waveform created by connecting the peak values of the modulated signal
The carrier frequency that contains the signal
Spurious signals that envelop nearby frequencies
The bandwidth of the modulated signal
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