Description : ECE Board Exam March 1996 The letter-number designation B8E is a form of modulation also known as ___________. A. pilot carrier system B. independent sideband emission C. lincomplex D. vestigial sideband transmission
Last Answer : B. independent sideband emission
Description : Refers to an emission designation for facsimile? A. J3E and F4E B. A3J and A4E C. A3E and F3C D. R3E and A3E
Last Answer : C. A3E and F3C
Description : Which symbol indicates that only one sideband is transmitted? A. A3E B. B8E C. C3F D. H3E
Last Answer : D. H3E
Description : Refers to the first symbol in an emission designation with an amplitude modulated main carrier represented by letter H. A. Single sideband suppressed carrier B. Double sideband full carrier C. Independent sideband D. Double sideband
Last Answer : B. Double sideband full carrier
Description : A form of single sideband emission where the degree of carrier suppression enable the carrier to be reconstituted and be used for demodulation. A. Half carrier single sideband emission B. Full carrier single sideband emission C. Reduced carrier single sideband emission D. Double sideband emission
Last Answer : C. Reduced carrier single sideband emission
Description : How many sidebands are present in the J3E mode? A. Two sidebands and a carrier B. One upper sideband C. One lower sideband D. Two carriers and one sideband
Last Answer : B. One upper sideband
Description : In the designation of bandwidth and emission, what letter in the first symbol represents a double-sideband type of modulation? A. A B. B C. C D. H
Last Answer : A. A
Description : A single sideband emission in which the degree of carrier suppression enables the carrier to be reconstituted and to be used for demodulation. A. Reduce carrier single sideband emission ... single sideband emission C. Full carrier single sideband emission D. Standard single sideband emission
Last Answer : A. Reduce carrier single sideband emission
Description : In radio signal emission designation, the fifth symbol means A. Details of signals B. Type of information transmitted C. Nature of multiplexing D. Nature of signal modulating the main carrier
Last Answer : C. Nature of multiplexing
Description : In radio regulation, the first symbol in the designation of radio emission is ______. A. Bandwidth B. Nature of signal(s) modulation the main carrier C. Type of modulation of the main carrier D. Type of information to be transmitted
Last Answer : C. Type of modulation of the main carrier
Description : Which transmit only one sideband? A. A3E B. 3AJ C. 11BE D. H3E
Description : The third symbol in the designation of radio emission under the ITU rules refers to A. Type of the modulation of the main carrier B. Bandwidth C. Nature of the signals modulating the main carrier D. Type of information to be transmitted
Last Answer : D. Type of information to be transmitted
Description : The first symbol in the designation of radio emission under the ITU rules to A. Nature of signals modulating the main carrier B. Type of information to be transmitted C. Bandwidth D. Type of modulation of the main carrier
Last Answer : D. Type of modulation of the main carrier
Description : Which determines the number of sideband components of FM? A. Modulation frequency B. Modulation index C. Carrier frequency D. All of these
Last Answer : B. Modulation index
Description : What carrier system multiplexes 96 voice band channels into a single 6.312 Mbps data signal? A. T1 carrier system B. T2 carrier system C. T1C carrier system D. T3 carrier system
Last Answer : B. T2 carrier system
Description : Type of emission produced by one of the early radio transmitter in trains of damped RF ac waves where its oscillator is coupled to a long wire antenna, normally used in radio telegraph and having sidebands on its carrier. A. Digital emission B. Key emission C. Cycle emission D. Spark emission
Last Answer : D. Spark emission
Description : Which of the following is referred to as a radio emission without sidebands A. Analog B. Carrier C. Data D. Voice
Last Answer : B. Carrier
Description : What is the required quality factor for an SSB filter with the following data: center frequency= 1 MHz, the desired attenuation level of the unwanted sideband= 80 dB and the separation between sidebands= 200 Hz? A. 1,250 B. 12,500 C. 125,000 D. 25,000
Last Answer : C. 125,000
Description : Type of modulation used in TV broadcast visual transmitter. A. Pulse modulation B. DSBFC C. Vestigial sideband D. SSBFC
Last Answer : C. Vestigial sideband
Description : For 100% modulation, power in each sideband is ________ of that of carrier? a) 50% b) 70% c) 60% d) 25%
Last Answer : Ans: D
Description : What digital carrier transmits a digital signal at 274.176 Mbps? A. T1 B. T3 C. T2 D. T4
Last Answer : D. T4
Description : A 1 Mhz carrier is amplitude modulated by a pure 200-Hz audio test tone. Which of the following combinations of frequencies represent the total content of the AM signal? A. 1 MHz and 200 Hz B. 1 MHz and 1000.2 kHz C. 999.8 kHz, 1000 kHz, and 1000.2 kHz D. 999.8 kHz and 1000.2 kHz
Last Answer : C. 999.8 kHz, 1000 kHz, and 1000.2 kHz
Description : What is meant by the term modulation index? A. The processor index. B. The ratio between the deviation of a frequency modulated signal and the modulating frequency. C. The FM signal-to-noise ratio. D. The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency.
Last Answer : B. The ratio between the deviation of a frequency modulated signal and the modulating frequency.
Description : What is the first symbol of a radio signal transmission having an amplitude modulated signal carrier, double side band? A. C B. B C. H D. A
Last Answer : D. A
Description : Referred to an oscillator signal “leak through” from a properly neutralized amplifier such as a master oscillator power amplifier. A. Carrier B. Stray signal C. Back wave D. Loss wave
Last Answer : C. Back wave
Description : A digital carrier facility used to transmit a DSI-formatted signal at 1.544. Mbps. A. T2 B. T1 C. T4 D. T3
Last Answer : B. T1
Description : A carrier signal has ______. A. Constant peak amplitude B. The information C. Frequency range 20-20000 Hz D. A varying amplitude
Last Answer : A. Constant peak amplitude
Description : Which of the following is not a baseband signal modulation? A. RF carrier B. Video System C. Audio signal D. Binary coded pulses
Last Answer : A. RF carrier
Description : The transformer signal coding method for T1 carrier is A. Binary B. NRZ C. Manchester D. Bipolar
Last Answer : D. Bipolar
Description : If the percentage modulation of an AM amplifier is 88% and the modulating signal is 1 volt, the carrier has an amplitude of _______________. A. 1.14 volts B. 0.88 volt C. 1.88 volts D. 0.12 volt
Last Answer : A. 1.14 volts
Description : ECE Board Exam March 1996 What is the IBM’s asynchronous data link protocol designation? A. 83 B B. 8A1 / 8B1 C. 93 B D. 9A1/ 9B1
Last Answer : A. 83 B
Description : How wide is the spectrum bandwidth of a single GSM carrier? A. 100 kHz B. 200 kHz C. 50 kHz D. 16 kHz
Last Answer : B. 200 kHz
Description : Modulation means A. Varying of information B. Utilization of a single transmission channel to carry multiple signals C. Varying of some parameters of a carrier such as its amplitude to transmit information D. Transmit pulses in DC form on a copper wire
Last Answer : C. Varying of some parameters of a carrier such as its amplitude to transmit information
Description : What is the advantage of single-sideband (ssb) transmission over AM transmission?
Last Answer : The same amount of intelligence can be transmitted with one sixth of the output power with less than one-half the bandwidth.
Description : With a single modulating tone, what is the amplitude of the sideband frequencies at 100-percent modulation?
Last Answer : One-half the amplitude of the carrier.
Description : The stability of transmitted signal from a simple Hartley oscillator single transmitter which is coupled to and antenna wire affected by ______. A. Chirping of oscillator B. Closer coupling between the oscillator and the antenna. C. Location of antenna D. Material of antenna
Last Answer : B. Closer coupling between the oscillator and the antenna.
Description : The first laser emitted a. Pulses of 694 nm red light b. A continuous red beam c. Pulses of white light from a helical flashlamp d. Spontaneous emission
Last Answer : a. Pulses of 694 nm red light
Description : Which of the following contributes to the broadening of laser emission bandwidth? a. Doppler shift of moving atoms and molecules b. Amplification within the laser medium c. Coherence of the laser light d. Optical pumping of the laser transition
Last Answer : a. Doppler shift of moving atoms and molecules
Description : Laser light is ______ emission. a. Coherent b. Stimulated c. Spontaneous d. Coherent and stimulated
Last Answer : d. Coherent and stimulated
Description : A large emission of hydrogen from the sun that affects communications. A. Solar flare B. Cosmic disturbance C. Ballistic disturbance D. Solar noise
Last Answer : A. Solar flare
Description : ____ is defined as any radiation of energy by means of electromagnetic wave. A. Emission B. Radiation C. Radio D. Broadcasting
Last Answer : A. Emission
Description : A modulation which does not follow the sine wave pattern, it produces undesirable harmonics such as spurious emission A. 0% modulated B. Over-modulated C. Unmodulated D. 100% modulated
Last Answer : B. Over-modulated
Description : Width of frequency band just enough to ensure the transmission of information at a required rate and quality required, and under a specified condition and class of emission. A. Occupied bandwidth B. Transmission bandwidth C. Necessary bandwidth D. Frequency bandwidth
Last Answer : C. Necessary bandwidth
Description : A third symbol emission which represent television. A. C B. D C. F D. A
Last Answer : C. F
Description : A third symbol radio emission which represent telephone transmission including sound broadcasting. A. W B. F C. C D. E
Last Answer : D. E
Description : What is emission F3F? A. Facsimile B. Modulated CW C. RTTY D. Television
Last Answer : D. Television
Description : With which emission type is the capture-effect most pronounced? A. CW B. FM C. SSB D. AM
Last Answer : B. FM
Description : The width of the frequency band which is just sufficient to ensure the transmission of information at the rate and with the quality required under a specified condition and class of emission. A. Occupied bandwidth B. Reference frequency C. Necessary bandwidth D. Frequency tolerance bandwidth
Description : Emission on a frequency or frequencies immediately outside the necessary bandwidth which result from the modulation process except spurious emission. A. Radiation B. Noise C. Out of the band D. Interference
Last Answer : C. Out of the band
Description : Production of radiation by a radio transmitting station A. Monitoring B. Emission C. Radiation D. Transmission
Last Answer : B. Emission