FCC General Exam Question Pool. Subelement 3BH. Signals and Emissions. 2 Questions. -------------------------------------------------- 3H 2.1 D What is the term for alteration of the Amplitude of an RF wave for the purpose of conveying information? A. Frequency Modulation. B. Phase Modulation. C. Amplitude Rectification. D. Amplitude Modulation. 3H 2.3 B What is the term for altering the phase of an RF wave for the purpose of conveying information? A. Pulse Modulation. B. Phase Modulation. C. Phase Rectification. D. Amplitude Modulation. 3H 2.4 D What is the term for alteration of the frequency of an RF wave for the purpose of conveying information? A. Phase Rectification. B. Frequency Rectification. C. Amplitude Modulation. D. Frequency modulation. 3H 3.1 D In what emission type does the instantaneous amplitude (envelope) of the radio frequency signal vary in accordance with the modulating AF? A. Frequency Shift Keying. B. Pulse Modulation. C. Frequency Modulation. D. Amplitude Modulation. 3H 3.2 A What determines the spectrum space occupied by each group of sideband frequencies generated by a correctly operating emission A3E transmitter? A. The audio frequencies used to modulate the transmitter. B. The phase angle between the Audio and Radio Frequencies being mixed. C. The radio frequencies used in the transmitter's VFO. D. The CW keying speed. 3H 4.1 C How much is the carrier supressed in an emission J3E transmission. A. No morehan 20 dB below peak output power. B. No more than 30 dB below peak output power. C. At least 40 dB below peak output power. D. At least 60 dB below peak output power. 3H 4.2 C What is one advantage of carrier supression in an emission A3E transmission? A. Only half the bandwidth is required for the same information content. B. Greater modulation percentage is obtainable with lower distortion. C. More power can be put into the sidebands. D. Simpler equipment can be used to receive a Double Sideband Supressed Carrier signal. 3H 5.1 A Which one of the telephony emissiona popular with Amateurs occupies the narrowest band of frequencies? A. Single Sideband Emissions. B. Double Sideband Emissions. C. Phase Modulated Emissions. D. Frequency Modulated Emissions. 3H 5.2 C Which emission type is produced by a telephony transmitter having a balanced modulator followed by a 2.5 kHz. bandpass filter? A. PM B. AM C. SSB D. FM 3H 7.2 B What emission is produced by a reactance modulator connected to an RF power amplifier? A. Miltiplex Modulation. B. Phase Modulation. C. Amplitude Modulation. D. Pulse modulation. 3H 8.1 D What purpose does the carrier serve in an emission A3E transmission? A. The carrier separates the sidebands so they don't cancel in the receiver. B. The carrier contains the the modulation information. C. The carrier maintains symmetry of the sidebands to prevent distortion. D. The carrier serves as a refrence signal for demodulation by an envelope detector. 3H 8.2 C What signal component aprears in the center of the frequency band of an emission A3E transmission? A. The lower sidebands. B. The subcarrier. C. The carrier. D. The pilot tone. 3H 9.1 C What sidebands are generated by an emission A3E transmitter with a 7250 kHz. carrier modulated less than 100% by an 800 Hz. pure Sine wave? A. 7250.8 kHz. and 7251.6 Khz. B. 7250.0 kHz. and 7250.8 Khz. C. 7249.2 kHz. and 7250.8 Khz. D. 7248.4 kHz. and 7249.2 Khz. 3H 10.1 B How many times over the maximum deviation is the bandwith of an emission F3E transmission? A. 1.5 times. B. At least 2. C. At least 4. D. The bandwith cannot be determined without knowing the exact carrier and modulating frequencies involved. 3H 10.2 D What is the total bandwith of an emission F3E transmission having 5 kHz. Deviation and 3 kHz. AF? A. 3 kHz. B. 5 kHz. C. 8 kHz. D. 16 kHz. 3H 11.1 A What happens to the shape of the RF envelope,as viewed on an oscilloscope, of an emission A3E transmission? A. The amplitude of the envelope increases and decreases in proportion to the modulating signal. B. The amplitude of the envelope remains constant. C. The brightness of the envelope increases and decreases in proportion to the modulating signal. D. The frequency of the envelope increases and decreases in proportion to the modulating signal. 3H 13.1 D What results when an emission J3E transmitter is overmodulated? A. The signal becomes louder with no other effects. B. The signal occupies less bandwith with poor high frequency responce. C. The signal has higher fidelity and improved signal to noise ratio. D. The signal becomes distorted and occupies more bandwith. 3H 13.2 B What results when an emission A3E transmitter is overmodulated? A. The signal becomes louder with no other effects. B. The signal becomes distorted and occupies more bandwith. C. The signal occupies less bandwith with poor high frequency responce. D. The transmitter's carrier frequency deviates. 3H 15.1 B What is the frequency deviation for a 12.21 MHz., Reactance Modulated oscillator in a 5kHz. deviation, 146.52 MHz. F3E transmitter? A. 41.67 HZ. B. 416.7 HZ. C. 5 kHz. D. 12 kHz. 3H 15.2 A What stage in a transmitter would translate a 5.3 MHz. input signal to 14.3 MHz.? A. A Mixer. B. A Beat Frequency Oscillator. C. A Frequency Multiplier. D. A Linear Translator. 3H 16.4 A How many frequency components are in the signal from an AF Shift keyer at any one instant? A. One. B. Two. C. Three. D. Four. 3H 16.5 C How is the frequency shift related to the keying speed in an FSK signal? A. The frequency shift in Hertz. must be at least four times the keying speed in WPM. B. The frequency shift must not exceed 15 Hz. per WPM of keying speed. C. Greater keying speeds require greater frequency shifts. D. Greater keying speeds require smaller frequency shifts. -------------------------------------------------- End of Subelement 3BH.