Acoustic & Broadcasting [MITRC refresher]

  1. Which best describe the sound wave?
  2. It may be longitudinal
  3. It is always transverse
  4. It is always longitudinal
  5. All of the above
  1. Which of the following can not travel through a vacuum?
  2. Electromagnetic wave
  3. Radio wave
  4. Soundwave
  5. Light wave
  1. Through which medium does sound travel fastest?
  2. Air
  3. Water
  4. Steel
  5. Mercury
  1. Speed that is faster than that of sound.
  2. Ultrasonic
  3. Supersonic
  4. Subsonic
  5. Transonic
  1. What is the speed of sound in air at 20°C?
  2. 1087 ft/s
  3. 1100 ft/s
  4. 1126 ft/s
  5. 200 ft/s
  1. Calculate a half wavelength sound for sound of 16000 Hz
  2. 35 ft
  3. 10 ft
  4. 0.035 ft
  5. 100 ft
  1. The lowest frequency that a human ear can hear is
  2. 5 Hz
  3. 20 Hz
  4. 30 Hz
  5. 20 Hz
  1. Sound that vibrates at frequency too high for the human ear to hear (over 20 kHz)
  2. Subsonic
  3. Ultrasonic
  4. Transonic
  5. Stereo
  1. The frequency interval between two sounds whose frequency ratio is 10
  2. Octave
  3. Half octave
  4. Third-octave
  5. Decade
  1. A 16 KHz sound is how many octaves higher than a 500 Hz sound
  2. 2
  3. 5
  4. 4
  5. 8
  1. Sound waves composed of but one frequency is a/an
  2. Infra sound
  3. Pure tone
  4. Structure borne
  5. Residual sound
  1. Sound wave has two main characteristics which are
  2. Highness and loudness
  3. Tone and loudness
  4. Pitch and loudness
  5. Rarefactions and compressions
  1. When waves bend away from straight lines of travel, it is called
  2. Reflection
  3. Diffraction
  4. Rarefaction
  5. Refraction
  1. The amplitude of sound waves, the maximum displacement of each air particle, is the property which perceive as _____ of a sound
  2. Pitch
  3. Intensity
  4. Loudness
  5. Harmonics
  1. It is the weakest sound that average human hearing can detect.
  2. SPL = 0 dB
  3. Threshold of hearing
  4. Reference pressure = 2 x 10-5N/m2
  5. A, b, c
  1. What is a device that is used to measure the hearing sensitivity of a person?
  2. Audiometer
  3. OTDR
  4. SLM
  5. Spectrum analyzer
  1. What is the device used in measuring sound pressure levels incorporating a microphone, amplification, filtering and a display.
  2. Audiometer
  3. OTDR
  4. SLM
  5. Spectrum analyzer
  1. What weighted scale in a sound level meter gives a reading that is most closely to the response of the human ear?
  2. Weighted scale A
  3. Weighted scale B
  4. Weighted scale C
  5. Weighted scale D
  1. For aircraft noise measurements, the weighting scale that is used is _____.
  2. Weighted scale A
  3. Weighted scale B
  4. Weighted scale C
  5. Weighted scale D
  1. It is the device used to calibrate an SLM?
  2. Microphone
  3. Pistonphone
  4. Telephone
  5. Filter
  1. _____ is the sound power measured over the area upon which is received.
  2. Sound pressure
  3. Sound energy
  4. Sound intensity
  5. Sound pressure level
  1. A measure of the intensity of sound in comparison to another sound intensity
  2. Phon
  3. Decibel
  4. Pascal
  5. Watts
  1. Calculate the sound intensity level in dB of a sound whose intensity is 0.007 W/m2.
  2. 95 dB
  3. 91 dB
  4. 98 dB
  5. 101 dB
  1. What is the sound pressure level for a given sound whose RMS pressure is 200/m2?
  2. 200 dB
  3. 20 dB
  4. 140 dB
  5. 14 dB
  1. What is the sound intensity for an RMS pressure of 200 Pascal?
  2. 90 W/m2
  3. 98 W/m2
  4. 108  W/m2
  5. 88 W/m2
  1. The sound pressure level is increased by _____ dB if the pressure is doubled.
  2. 3
  3. 4
  4. 5
  5. 6
  1. The sound pressure level is increased by _____ dB if the intensity is doubled.
  2. 3
  3. 4
  4. 5
  5. 6
  1. If four identical sounds are added what is the increase in level in dB?
  2. 3
  3. 4
  4. 5
  5. 6
  1. The transmission of sound from one room to an adjacent room, via common walls, floors or ceilings.
  2. Flanking transmission
  3. Reflection
  4. Refraction
  5. Reverberation
  1. _____ is the continuing presence of an audible sound after the sound source has stop.
  2. Flutter echo
  3. Sound concentration
  4. Sound shadow
  5. Reverberation
  1. Required time for any sound to decay to 60 dB
  2. Echo time
  3. Reverberation time
  4. Delay time
  5. Transient time
  1. A room containing relatively little sound absorption
  2. Dead room
  3. Anechoic room
  4. Live room
  5. Free-field
  1. A room in which the walls offer essentially 100% absorption, therefore simulating free field conditions.
  2. Dead room
  3. Anechoic room
  4. Live room
  5. Closed room
  1. Calculate the reverberation time of the room, which has a volume of 8700 ft3 and total sound absorption 140 sabins.
  2. 0.3 sec
  3. 3.5 sec
  4. 3 sec
  5. 0.53 sec
  1. It is an audio transducer that converts acoustic pressure in air into its equivalent electrical impulses
  2. Loudspeaker
  3. Amplifier
  4. Baffle
  5. Microphone
  1. _____ is a pressure type microphone with permanent coil as a transducing element.
  2. Dynamic
  3. Condenser
  4. Magnetic
  5. Carbon
  1. A microphone which has an internal impedance of 25 kΩ is _____ type.
  2. High impedance
  3. Low impedance
  4. Dynamic
  5. Magnetic
  1. A microphone that uses the piezoelectric effect
  2. Dynamic
  3. Condenser
  4. Crystal
  5. Carbon
  1. _____ is a type of loudspeaker driver with an effective diameter of 5 inches used at midrange audio frequency.
  2. Tweeter
  3. Woofer
  4. Mid-range
  5. A or C
  1. _____ is measure of how much sound is produced from the electrical signal.
  2. Sensitivity
  3. Distortion
  4. Efficiency
  5. Frequency response
  1. It describes the output of a microphone over a range of frequencies.
  2. Directivity
  3. Sensitivity
  4. Frequency response
  5. All of the above
  1. A loudspeaker radiates an acoustic power of 1 mW if the electrical input is 10 W. What is its rated efficiency?
  2. -10 dB
  3. -20 dB
  4. -30 dB
  5. -40 dB
  1. An amplifier can deliver 100 W to a loudspeaker. If the rated efficiency of the loudspeaker is -60 dB. What is the maximum intensity 300 ft from it?
  2. 10 dB
  3. 20 dB
  4. 30 dB
  5. 40 dB
  1. Speaker is a device that
  2. Converts sound waves into current and voltage
  3. Converts current variations into sound waves
  4. Converts electrical energy to mechanical energy
  5. Converts electrical energy to electromagnetic energy
  1. The impedance of most drivers is about _____ ohms at their resonant frequency.
  2. 4
  3. 6
  4. 8
  5. 10
  1. It is a transducer used to convert electrical energy to mechanical energy.
  2. Microphone
  3. Baffle
  4. Magnetic assemble
  5. Driver
  1. It is an enclosure used to prevent front and back wave cancellation.
  2. Loudspeaker
  3. Driver
  4. Baffle
  5. Frame
  1. A circuit that divides the frequency components into separate bands in order to have individual feeds to the different drivers.
  2. Suspension system
  3. Dividing network
  4. Magnet assembly
  5. Panel board
  1. _____ is early reflection of sound.
  2. Echo
  3. Pure sound
  4. Reverberation
  5. Intelligible sound
  1. Noise reduction system used for film sound in movie.
  2. Dolby
  3. DBx
  4. dBa
  5. dBk
  1. Using a microphone at less than the recommended working distance will create a _____ which greatly increases the low frequency signals.
  2. Roll-off
  3. Proximity effect
  4. Drop out
  5. None of the choices
  1. What is the unit of loudness?
  2. Sone
  3. Phon
  4. Decibel
  5. Mel
  1. A unit of noisiness related to the perceived noise level
  2. Noy
  3. dB
  4. Sone
  5. Phon
  1. What is the loudness level of a 1KHz tone if its intensity is     1 x 10-5W/cm2?
  2. 100 phons
  3. 105 phons
  4. 110 phons
  5. 100 phons
  1. What is the process of sending voice, speech, music or image intended for reception by the general public?
  2. Navigation
  3. Telephony
  4. Broadcasting
  5. Mixing
  1. What is the frequency tolerance for the RF carrier in the standard AM radio broadcast band?
  2. Zero
  3. 20 Hz
  4. 10 Hz
  5. 20 KHz
  1. The transmitting antenna for an AM broadcast station should have a _____ polarization.
  2. Vertical
  3. Horizontal
  4. Circular
  5. Elliptical
  1. The part of a broadcast day from 6 PM to 6 AM local time
  2. Daytime
  3. Nighttime
  4. Bed time
  5. Experimental period

 

  1. The service area where the signal is not subject to fading and co-channel interference.
  2. Primary Service Area
  3. Secondary Service Area
  4. Intermittent Service Area
  5. Quarternary Service Area
  1. It is a resistive load used in place of an antenna to test a transmitter under normal loaded condition without actually radiating the transmitter’s output signal.
  2. Auxiliary Tx
  3. Main Tx
  4. Secondary Tx
  5. Artificial Antenna
  1. The operating power of the auxiliary transmitter shall not be less than _____% or never greater than the authorized operating power of the main transmitter.
  2. 5
  3. 10
  4. 15
  5. 20

 

  1. What are the frequency limits of the MF BC band?
  2. 300-3000 kHz
  3. 3-30 MHz
  4. 535-1605 kHz
  5. 88-108 MHz

 

  1. The center to center spacing between two adjacent stations in the Phil. AM BC band is ____.
  2. 9 kHz
  3. 200 kHz
  4. 36 kHz
  5. 800 kHz
  1. How many AM stations can be accommodated in a 150-kHz bandwidth if the highest modulating frequency is 10 kHz?
  2. 10
  3. 15
  4. 7
  5. 14
  1. Short wave broadcasting operates in what band?
  2. MF
  3. HF
  4. VHF
  5. VLF
  1. What does the acronym STL stand for?
  2. Station-to-link
  3. Signal-to-loss-ratio
  4. Shout-to-live
  5. Studio-to-transmitter-link
  6. One of the main considerations in the selection of antenna site is (AM)
  7. Conductivity of the soil
  8. Height of the terrain
  9. Elevation of the site
  10. Accessibility
  1. One of the broadcast transmission auxiliary services is:
  2. Remote pick-up
  3. STL
  4. Communication, Coordination and Control
  5. All of the above                
  1. What is the spacing between any two adjacent channels in the FM broadcast band?
  2. 20 KHz
  3. 36 KHz
  4. 200 KHz
  5. 800 KHz
  1. The first channel in the FM BC band has a center frequency of
  2. 88 MHz
  3. 88.1 MHz
  4. 88.3 MHz
  5. 108 MHz
  1. What is the radio transmission of two separate signals, left, and right, used to create a multidimensional effect on the receiver?
  2. SCA
  3. Stereo system
  4. Pilot transmission
  5. Monophonic transmission
  6. The carrier frequency tolerance for FM broadcasting is _____.
  7. 25 kHz
  8. 2 kHz
  9. 20 kHz
  10. 30 kHz
  1. What is the modulation used by the stereophonic subcarrier?
  2. FM
  3. PM
  4. ISB
  5. DSB
  1. What is the pilot signal for stereo FM?
  2. 4.25 MHz
  3. 10 kHz
  4. 19 KHz
  5. 38 KHz
  1. With stereo FM transmission, does a monaural receiver produce all the sounds that a stereo does?
  2. Yes
  3. No
  4. Either a or b
  5. Neither a or b
  1. Where is de-emphasis added in a stereo FM system?
  2. Before the matrix at the TX
  3. Before the matrix at the RX
  4. After the matrix at the TX
  5. After the matrix at the RX
  1. Where is the pre-emphasis added in a stereo FM system?
  2. Before the matrix at the TX
  3. Before the matrix at the RX
  4. After the matrix at the TX
  5. After the matrix at the RX
  1. The normal frequency for an SCA subcarrier is _____ KHz.
  2. 67
  3. 76
  4. 38
  5. 19
  1. A monaural FM receiver receives only the _____ signal of a stereo multiplex transmission.
  2. L + R
  3. L – R
  4. Both a & b
  5. 67 KHz
  1. When fed to the stereo FM modulator, in what form are the L – R signals?
  2. AF
  3. DSBSC
  4. 19 kHz
  5. 38 kHz
  1. An additional channel of multiplex information that is authorized by the FCC for stereo FM radio stations to feed services such as commercial-free programming to selected customers.
  2. STL
  3. EBS
  4. EIA
  5. SCA
  1. The class of FM station, which has an authorized radiated power not exceeding 125 KW:
  2. Class C
  3. Class A
  4. Class D
  5. Class B
  1. An FM broadcast station, which has an authorized transmitter power not exceeding 10 KW and ERP not exceeding 30 KW:
  2. Class D
  3. Class C
  4. Class A
  5. Class B        
  1. A class of FM station which is limited in antenna height of 500 ft. above average terrain
  2. Class D
  3. Class C
  4. Class A
  5. Class B        
  1. What type of broadcast service might have their antennas on top of hills?
  2. FM
  3. AM
  4. TV
  5. A & C 
  1. How are guardbands allocated in commercial FM stations?
  2. 25 kHz on either sides of the transmitting signal
  3. 50 kHz on each side of the carrier
  4. 75 kHz deviation
  5. 15 kHz modulation
  1. How many commercial FM broadcast channels can fit into the bandwidth occupied by a commercial TV station?
  2. 10
  3. 20
  4. 30
  5. 40
  1. How many international commercial AM broadcast channels can fit into the bandwidth occupied by a commercial TV station?
  2. 100
  3. 200
  4. 125
  5. 600   
  1. What kind of modulation is used for the sound portion of a commercial broadcast TV transmission?
  2. PM
  3. FM
  4. C3F
  5. AM
  1. Estimate the bandwidth occupied by the sound portion of a TV transmission in US.
  2. 25 kHz
  3. 800 kHz
  4. 80 kHz
  5. 200 kHz
  1. What is the main reason why television picture signal uses amplitude modulation, while voice is frequency modulated?
  2. Better efficiency
  3. Eliminate attenuation of both video and audio
  4. Maintain synchronized scanning between transmit and received video
  5. To minimize interference between signals at received end                        
  1. The picture and sound carrier frequencies in a TV receiver are _____ respectively.
  2. 41.25 MHz, 45.75 MHz
  3. 45.25 MHz, 41.75 MHz
  4. 41.75 MHz, 45.25 MHz
  5. 45.75 MHz, 41.25 MHz               
  1. What is the separation between visual and aural carrier in TV broadcasting?
  2. 1.25 MHz
  3. 4.5 MHz
  4. 5.75 MHz
  5. 0.25 MHz
  1. What is the separation between the lower limit of a channel and the aural carrier?
  2. 1.25 MHz
  3. 4.5 MHz
  4. 5.75 MHz
  5. 0.25 MHz
  1. What is the visual carrier for channel 12?
  2. 205.25 MHz
  3. 55.25 MHz
  4. 65.75 MHz
  5. 59.75 MHz
  1. What is the aural carrier for channel 3?
  2. 61.25 MHz
  3. 55.25 MHz
  4. 65.75 MHz
  5. 59.75 MHz
  1. What is color subcarrier for channel 2?
  2. 68.83 MHz
  3. 211.25 MHz
  4. 58.83 MHz
  5. 214.83 MHz
  1. If the sound carrier for UHF channel 23 is 529.75 MHz, what is the frequency of the tuner’s local oscillator, when turned to this channel?
  2. 571 MHz
  3. 511 MHz
  4. 498 MHz
  5. 500 MHz
  1. What is the frequency tolerance in the color carrier of TV broadcasting?
  2. 2 kHz
  3. 20 Hz
  4. 10 Hz
  5. 1 kHz
  1. What is the exact picture carrier frequency for frequency for channel 7 offset by – 10 KHz?

a          175.25 MHz

b          175.26 MHz

c           174 MHz

d          175.24 MHz

  1. TV channels 7, 11 and 13 are known as _____.
  2. Mid band UHF
  3. Low band UHF
  4. High band VHF
  5. low band UHF
  1. What is eliminated by using interlaced scanning?
  2. Noise
  3. Excessive BW
  4. Frame
  5. Flicker
  1. What percentage of the primary colors used in color TV are needed to produce the brightest white?
  2. 30% red, 59% green, 11% blue
  3. 33% red, 33% green, 33% blue
  4. 50% red, 28% green, 22% blue
  5. 58% red, 20% green, 22% blue
  1. The color with the most luminance is
  2. Red
  3. Yellow
  4. Green
  5. Blue
  1. Suppose the signal from a color camera has R=0.8, G=0.4 and B=0.2, where 1 represents the maximum signal possible. Determine the value at the luminance signal
  2. 0.498
  3. 0.254
  4. 0.1325
  5. 1.4
  1. In the previous problem, calculate the chrominance signal
  2. 0.305
  3. 0.304
  4. 0.498
  5. 0.022
  1. The three complementary colors are:
  2. White, yellow, cyan
  3. Black, white, gray
  4. Yellow, magenta, cyan
  5. Violet, indigo, fushcia
  1. When the colors Magenta and Yellow are mixed the resultant color is:
  2. Red
  3. White
  4. Blue
  5. Green
  1. Which of the following consist of two of the three primary colors in television signal? a) red, b) violet, c) yellow, and   d) blue
  2. A and B
  3. B and C
  4. C and D
  5. A and D
  1. The studio camera produces a luminance signal that contains information about
  2. The musical content
  3. The speech content
  4. The brightness of the scene
  5. The color content of the scene
  1. Brightness variations of the picture information are in which signal?
  2. I
  3. Q
  4. Y
  5. Z
  1. Which of the following is the color video signal transmitted as amplitude modulation of the 3.58 MHz C signal with bandwidth of 0 to 1.3 MHz?
  2. I signal
  3. Q signal
  4. Y signal
  5. X signal
  1. Which of the following is the color video signal transmitted as amplitude modulation of the 3.58 MHz C signal in quadrature with bandwidth of 0 to 0.5 MHz?
  2. I signal
  3. Q signal
  4. Y signal
  5. Z signal
  1. The _____ affects the difference between black and white on the picture tube and controls the gain of the video amplifier
  2. Brightness control
  3. Volume control
  4. Power control
  5. Contrast control
  1. Which of the following is not a requirement for a color TV signal?
  2. compatibility with b lack and white receivers
  3. Within 6 MHz bandwidth
  4. Simulate a wide variety of colors
  5. Functional with baron super antenna
  1. How many electron beams actually leave the electron gun of a single-gun color CRT?
  2. 1
  3. 2
  4. 3
  5. 1/3
  1. What is the difference between the sound carrier and color subcarrier frequencies?
  2. 1.25 MHz
  3. 3.58 MHz
  4. 4.5 MHz
  5. 0.92 MHz
  1. What does aspect ratio mean?
  2. Ratio of the screen width to its height
  3. Ratio of the screen height to its width
  4. Ratio of the screen diagonal to its width
  5. Ratio of the screen diagonal to its height
  1. What is the aspect ratio for HDTV system?
  2. 4/3
  3. 9/7
  4. 19/6
  5. 16/9
  1. The signal that will give the exact color wavelength is _____.
  2. Hue
  3. Saturation
  4. Carrier
  5. Monochrome
  1. Which of the following represents the intensity of a given color?
  2. Hue
  3. Saturation
  4. Carrier
  5. Monochrome
  1. The _____ ensures that the electron beam will strike the correct phosphor dot on the TV screen.
  2. Coating
  3. Aperture Mask
  4. Diplexer
  5. Duplexer
  1. In a TV receiver, what is the horizontal signal frequency?
  2. 30 Hz
  3. 60 Hz
  4. 15750 Hz
  5. 157625 Hz
  1. In a TV receiver, what is the vertical signal frequency?
  2. 30 Hz
  3. 60 Hz
  4. 15750 Hz
  5. 157625 Hz
  1. What scheme is employed to cause the electron beam in the TV receiver and the electron beam in the studio camera to track identically?
  2. Interlacing
  3. NTSC
  4. Interleaving
  5. Transmission of sync pulses
  1. Equalizing pulses in TV are sent during
  2. Horizontal blanking
  3. Vertical blanking
  4. The serrations
  5. Equalizing intervals
  6. What is the return of the electron beam in a CRT from right to left or from bottom to top?
  7. Relay
  8. Flyback
  9. Utilization
  10. Resolution
  1. What is the North American TV standard video?
  2. PAL
  3. SECAM
  4. NTSC
  5. FCC
  1. What is the maximum allowable frequency deviation in the audio section of a TV signal for PAL/SECAM?
  2. 25 kHz
  3. 50 kHz
  4. 75 kHz
  5. 100 kHz
  1. What is the frame frequency in the US TV system?
  2. 30 Hz
  3. 60 Hz
  4. 15750 Hz
  5. 157625 Hz
  1. What is the highest video frequency set by the FCC for commercial TV?
  2. 4.2 MHz
  3. 15 MHz
  4. 6 MHz
  5. 5.5 MHz
  1. What determines the maximum number of vertical picture elements?
  2. Number of frames per second
  3. Number of lines on the screen
  4. Number of pixels
  5. Number of fields per second
  1. How many horizontal lines are used to develop a TV raster?
  2. 615
  3. 525
  4. 750
  5. 15750
  1. The channel width in the U.S. TV system is :
  2. 2 MHz
  3. 6 MHz
  4. 7 MHz
  5. 8 MHz
  1. It is the popular TV camera designed with much smaller package and lower cost than its earlier designs
  2. Image orthicon
  3. Iconoscope
  4. Vidicon
  5. Plumbicon
  1. In a composite video signal, what is the relationship between the amplitude of the signal and the intensity of the electron beam in the receiver picture tube?
  2. The greater the amplitude the darker the picture
  3. The lower the amplitude the darker the picture
  4. The greater the amplitude the lighter the picture
  5. No effect
  1. If there are 625 lines per TV picture then the number of lines per field are:
  2. 1250
  3. 312.5
  4. 625
  5. 2500
  1. What is the process of placing the chrominance signal in the band space between portions of the luminance signal?
  2. Interlacing
  3. Fitting
  4. Sneaking
  5. Interleaving
  1. How much time elapses between the start of one horizontal sync pulse and the next?
  2. 10.2 μs
  3. 63.5 μs
  4. 16.67 μs
  5. 100 μs
  1. Which of the following frequencies is wrong?
  2. 15,750 Hz for horizontal sync and scanning
  3. 60 Hz for vertical sync and scanning
  4. 31,500 Hz for the equalizing pulses and serrations in the vertical sync pulse
  5. 31,500 Hz for the vertical scanning frequency
  1. The camera tube that uses selenium, arsenic and tellurium
  2. Plumbicon
  3. Vidicon
  4. Saticon
  5. Silicon Vidicon
  1. The components of composite video signal are:
  2. Chroma signal
  3. Blanking pulse
  4. Synchronizing pulse
  5. All of these
  1. What is the smallest amount of information that can be displayed on a television screen?
  2. Blip
  3. Burst
  4. Pixel
  5. Bits
  1. It is the quality of the TV picture after imperfections
  2. Aspect ratio
  3. Utilization ratio
  4. A1
  5. Monochrome
  1. What section of a TV receiver determines the bandwidth and produces the most signal gain?
  2. RF amplifier
  3. Audio amplifier
  4. IF amplifier
  5. Tuned circuit

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About Abbas

Born at a very young age, analogue at birth, digital by design, naturally and artificially flavored, recommended by 4 out of 5 people that recommend things and currently studying Electronics and Communications Engineering by Passion and Profession in the Philippines.

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