An antenna located in a city is a source of radio waves. How much time does it take the wave to reach a town 12,000 km away from the city?
a. 36 s b. 20 us c. 20 ms d. 40 ms
Description : What type of communication use Radio waves: a. Unicast b. Both (a) and (c) can be used c. Multicast d. None of the above
Last Answer : What type of communication use Radio waves: Multicast
Description : A half wavelength Dipole antenna has _________ Radiation Pattern a. Hemispherical b. Omni-Directional c. Isotropic d. End fire
Last Answer : A half wavelength Dipole antenna has Omni-Directional Radiation Pattern
Description : Radio frequency ranges from 30MHz to 1GHz and it is suitable for: a. Point to point transmission b. Omni directional transmission c. Local point to point transmission d. None of the above
Last Answer : Radio frequency ranges from 30MHz to 1GHz and it is suitable for: Local point to point transmission
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 : What is meant by referring to electromagnetic waves as having circular polarization? A. The electric field is bent into a circular shape. B. The electric field rotates C. The electromagnetic wave continues to circle the earth D. The electromagnetic wave has been generated by a quad antenna
Last Answer : B. The electric field rotates
Description : For a space wave transmission, the radio horizon distance of a receiving antenna with a height of 64 meters is approximately A. 8 km B. 32 km C. 64 km D. 256 km
Last Answer : B. 32 km
Description : The polarization of a radio wave: A. Is perpendicular to the electrostatic field of the antenna B. Is the same direction as the electrostatic field of the antenna. C. Is the same direction ... field of the antenna. D. Is perpendicular to both the electrostatic and magnetic fields of the antenna.
Last Answer : B. Is the same direction as the electrostatic field of the antenna.
Description : What type of transmission is radiated from an aircraft’s radio altimeter antenna? A. An amplitude modulated continuous wave B. A pulse position modulated UHF signal C. A differential phase shift keyed UHF signal D. A frequency modulated continuous wave
Last Answer : D. A frequency modulated continuous wave
Description : For a space wave transmission, the radio horizon distance of a transmitting antenna with a height of 100 meters is approximately: A. 10 km B. 40 km C. 100 km D. 400 km
Last Answer : B. 40 km
Description : Which of the following parts of the radio receiver represent the component that extracts the desire RF signal from the electromagnetic wave? A. AF amplifier B. Antenna C. Detector D. Crystal
Last Answer : B. Antenna
Description : Radio wave concentration in the direction of the signal emitted by a directional antenna. A. Back lobe radiation B. Side lobe radiation C. Major lobe radiation D. Transmitted signal
Last Answer : C. Major lobe radiation
Description : Sound waves transmitted from a source are sometimes weak when they reach the detector. What instrument is needed to boost the weak signal?
Last Answer : An amplifier.
Description : Long distance short-wave radio broad casting uses which waves? -Do You Know?
Last Answer : answer:
Description : Why are we able to hear shortwave broadcasts better than long wave broadcasts? (a) Short wave broadcasts are made by nearby radio stations (b) Short waves are unaffected by atmospheric ... convention, short waves are meant for long distances whereas long waves are reserved for short distances
Last Answer : Ans:(c) Direction: In the following question, a statement of Assertion (A) is given followed by corresponding Reason (R), just below it. Read the statements carefully and mark the correct answer: (a) If both A and ... true but R is not the correct explanation of A. (c) If A is true but R is false
Description : Why are we able to hear short wave broadcasts better than long wave broadcasts? (1) Short waves are more energetic than long waves (2) Short waves are unaffected by atmospheric disturbances ... convention, short waves are meant for long distances, whereas long waves are reserved for short distances
Last Answer : (1) Short waves are more energetic than long waves Explanation: Shortwave radio is used for broadcasting of voice and music, and longdistance communication to ships and aircraft, or to remote areas ... wired communication or other radio services and that's why it is more energetic than long waves.
Description : Long distance short-wave radio broad casting uses which waves?
Last Answer : Ionospheric wave
Description : Which wave has the highest frequency? w) microwaves x) infrared waves y) ultraviolet waves z) radio waves
Last Answer : ANSWER: Y -- ULTRAVIOLET WAVES
Description : Why are we able to hear short wave broadcasts better than long wave broadcasts ? (1) Short waves are more energetic than long waves. (2) Short waves are unaffected by atmospheric ... convention, short waves are meant for long distances, whereas long waves are reserved for short distances.
Last Answer : Short waves are more energetic than long waves.
Description : What connecting link is used to transfer energy from a radio transmitter to its antenna located on
Last Answer : Transmission line.
Description : If someone were to write a biography about us, the following could be reported: #1 - All athletes, to reach their peak performance, must do me. #2 - Behind a groom is a best man, but behind a ... me in the town of Hooterville. Based on the biographical information above --- Who/what are we? -Riddles
Last Answer : We are Trains.
Description : A receiver is located 64 km from a space wave transmitting antenna that is 100 meters high. Find the required height of the receiving antenna. A. 36 meters high B. 64 meters high C. 100 meters high D. 182.25 meters high
Last Answer : A. 36 meters high
Description : How long will it take for p waves to hit a town that is 25 kilometers away?
Last Answer : Feel Free to Answer
Description : An evanescent mode occurs when: a. A wave is attenuated rather than propagated. b. The propagation constant is purely imaginary. c. m = 0 = n so that all field components vanish. d. The wave frequency is the same as the cutoff frequency.
Last Answer : An evanescent mode occurs when: A wave is attenuated rather than propagated.
Description : At Service provider end IMEI number of MS is basically stored in: a. HLR b. VLR c. AUC d. EIR
Last Answer : At Service provider end IMEI number of MS is basically stored in: a. HLR b. VLR c. AUC d. EIR
Description : Which cable connects the subscriber telephone to the nearest end office in the local loop. a. Coaxial b. Fiber-optic c. Twisted-pair d. Both (b) and (c)
Last Answer : Which cable connects the subscriber telephone to the nearest end office in the local loop. a. Coaxial b. Fiber-optic c. Twisted-pair d. Both (b) and (c)
Description : Unlike coax and twisted pair, optical fibers are immune to a. High-frequency transmission b. Signal attenuation c. Power loss d. Electromagnetic interference
Last Answer : Unlike coax and twisted pair, optical fibers are immune to Electromagnetic interference
Description : Regenerative repeaters are placed along the communication path to control: a. Power b. Noise c. Frequency d. Amplitude
Last Answer : Regenerative repeaters are placed along the communication path to control: Noise
Description : The Fourier transform of a gate pulse is: a. Sinc function b. Triangular function c. Gate function d. Unit step unction
Last Answer : The Fourier transform of a gate pulse is: Sinc function
Description : Which of these materials requires the least value of magnetic field strength to magnetize it? a. Nickel b. Silver c. Tungsten d. Sodium chloride
Last Answer : Which of these materials requires the least value of magnetic field strength to magnetize it? a. Nickel b. Silver c. Tungsten d. Sodium chloride
Description : Where the poles should be placed on the unit circle for stable filter? a. Outside b. Inside c. both a & b d. none of the above
Last Answer : Where the poles should be placed on the unit circle for stable filter? a. Outside b. Inside c. both a & b d. none of the above
Description : Fast fading occurs if the channel____________ changes rapidly within the symbol duration. a. Bandwidth b. Frequency c. Impulse response d. None of the above
Last Answer : Fast fading occurs if the channel Impulse response changes rapidly within the symbol duration.
Description : As we know when there is a joint in optical fiber then there will be some loss then this loss be minimized by a. Using index matching fluid in the gap b. Making V-grooved splicing c. Both (a)and (b) d. Making carefully polishing
Last Answer : As we know when there is a joint in optical fiber then there will be some loss then this loss be minimized by Using index matching fluid in the gap
Description : Turning up the transmit power, or utilizing a high-gain antenna to reach wireless users from a distance, increases your exposure to ______________________.?
Last Answer : Turning up the transmitter power is a good way to insure that more cellphones, farther away, can hear the base station. But it doesn't to anything to help the base station hear the cellphones that ... narrower beam-width. So it works farther out, but only through a narrower 'window' of directions.
Description : The antenna radiates _____ polarized waves when the transmitter antenna is horizontally installed. A. Vertically B. negatively C. horizontally D. circularly
Last Answer : C. horizontally
Description : What is the process called when waves reach shallow water and are bent and tend to become parallel to the shore?
Last Answer : This is an example of refraction, as the waves are being turnedfrom their original path. This can result in the formation of alongshore (parallel) current that flows seaward as a "riptide."
Description : If Garrett counts the number of waves that reach the shore over a 10 second period what property of the waves is he measuring?
Last Answer : He is measuring the frequency of the wave. To get his answer hemust divide his count by 10 to give cycles per second.
Description : It is an average power of a radio transmitter supplied to the antenna transmission line taken during a long sufficient interval of time and compared with the lowest frequency encountered in the modulation ... operating conditions. A. Carrier power B. Rated power C. Mean power D. Peak envelop power
Last Answer : C. Mean power
Description : Is there an easy way to increase the reception on a radio with one of those simple, single wire antenna?
Last Answer : Attach it to yourself. .. it will boost the signal.
Description : What antenna do I need for my CB radio?
Last Answer : The main thing to remember for CB radio antennas is that taller antennas will work better. If this is for a vehicle, select a tall antenna where at least 50 percent of it will be above the roof line. You will have the best range this way.
Description : How many personnel are required to assemble and erect the Rapid Airfield Damage Assessment System (RADAS) antenna and radio tripod?
Last Answer : 3
Description : In radio-communication, the signals emitted by transmitting antenna are reflected on – (1) stratosphere (2) ozonosphere (3) ionosphere (4) troposphere
Last Answer : (3) ionosphere Explanation: The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emitted by an antenna from a ... on the surface of Earth in the following two ways: ground wave propagation and sky wave propagation.
Description : A final amplifier of a radio transmitter draws 250 mA of plate current when the plate supply voltage is 1400 volts. If the plate circuit efficiency is 80% and the transmitter is connected to an antenna having a feed impedance of 70 ohms, ... at the feed-point? A. 4.0 A B. 2.2 A C. 1.25 A D. 2.0 A
Last Answer : D. 2.0 A
Description : How far away is the radio horizon of an antenna 100ft high? A. 14.14 mi B. 40km C. 14.14 km D. 40 mi
Last Answer : A. 14.14 mi
Description : In Radio Communication, the signals emitted by transmitting antenna are reflected on
Last Answer : Ionosphere
Description : What is a dummy antenna? A. One which is used as a reference for gain measurements B. And antenna used for hand-held radio C. An non-directional transmitting antenna D. A non-radiating load for a transmitter used for testing
Last Answer : D. A non-radiating load for a transmitter used for testing
Description : Referred to as an average power from the radio transmitter supplied to the antenna transmission line taken during one radio frequency cycle under no modulation. A. Carrier power B. Rated power C. Peak envelop power D. Mean power
Last Answer : A. Carrier power
Description : Average power of a radio transmitter supplied to the antenna transmission line by a transmitter during one radio frequency cycle taken under the condition of no modulation. A. Peak envelop power B. Rated power C. Carrier power D. Mean power
Last Answer : C. Carrier power
Description : What type of amplifier would be used to amplify the signal from a radio antenna?
Last Answer : An rf voltage amplifier.
Description : An automobile needs an antenna for its radio to play properly because: w) the automobile's tires insulate it from the ground. x) the automobile's body acts as a Faraday cage. y) when the ... signal appears changed with respect to when it is at rest. z) the transmitter also uses an antenna.
Last Answer : ANSWER: X -- THE AUTOMOBILE'S BODY ACTS AS A FARADAY CAGE.