Description : A pair of current-carrying conductors is not considered a transmission line unless it is at least ___ λ long at the signal frequency. A. 0.1 B. 0.3 C. 0.2 D. 0.4
Last Answer : A. 0.1
Description : What is the phase coefficient in radians per unit length of a transmission line at the frequency of 10 MHz if the velocity of propagation is 2.5x108 m/s? A. 0.25 B. 2.5 C. 0.35 D. 3.5
Last Answer : A. 0.25
Description : A radio frequency in the ultra high frequency band of the radio spectrum band. A. 235.50 MHz B. 450.50 MHz C. 150.50 GHz D. 0.31250 GHz
Last Answer : D. 0.31250 GHz
Description : What is the physical length of the above transmission line at 3/8λ long? A.0.82 m B. 0.82 ft C. 0.82 in D. 0.82 cm
Last Answer : B. 0.82 ft
Description : Determine from the following radio frequency that falls under the very high frequency band of the radio spectrum. A. 345.00 MHz B. 144.50 MHz C. 235.50 MHz D. 450.00 MHz
Last Answer : C. 235.50 MHz
Description : Determine the gain of a 6 ft. parabolic dish operating at 1800 MHz. A. 30 dB B. 11.2 dB C. 15.5 dB D. 28.17 dB
Last Answer : D. 28.17 dB
Description : What would be the physical length of a tpical coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz? A. 20 meters B. 3.51 meters C. 2.33 meters D. 0.25 meter
Last Answer : B. 3.51 meters
Description : What is the actual length in feet of a one-quarter wavelength of a coax with a velocity factor of 0.68 to 30 MHz? A. 19.26 B. 5.6 C. 17.82 D. 16.97
Last Answer : B. 5.6
Description : What is the actual length in feet of a one-quarter wavelength of a coax with a velocity factor of 0.695 at 45 MHz? A. 17.82 B. 19.26 C. 16.28 D. 16.97
Last Answer : C. 16.28
Description : The frequency of operation of a dipole antenna cut to a length of 3.4 m. A. 88 MHz B. 44 MHz C. 22 MHz D. 11 MHz
Last Answer : B. 44 MHz
Description : The frequency of operation of a dipole antenna cut to length of 3.4 m. A. 42.9 MHz B. 61.3 MHz C. 38.5 MHz D. 53.5 MHz
Last Answer : A. 42.9 MHz
Description : A transmission line consisting of two conductors that have equal resistance per unit length. A. Unbalanced line B. Open-wire line C. Balanced line D. Coaxial line
Last Answer : C. Balanced line
Description : What is transit time (time delay) of a 50-ft length transmission line of the above problem? A. 50 ns B. 100 ns C. 75 ns D. 65 ns
Last Answer : C. 75 ns
Description : At a certain time, the MUF for transmission at an angle of incidence of 75° is 17 MHz. What is the critical frequency? A. 4.4 MHz B. 3.5 MHz C. 6.5 MHz D. 1.5 MHz
Last Answer : A. 4.4 MHz
Description : This type of transmission permits communication in the frequency range from 30 to 60 MHz and over distances from about 1000 to 2000 km. A. Troposcatter B. Ionospheric scatter C. Ducting D. Microwave
Last Answer : B. Ionospheric scatter
Description : Type of transmission path that permits communication in the frequency range from 30 to 60 MHz and over distances form about 1000 to 2000 km. A. Ducting B. Ionospheric scatter C. Microwave D. Troposcatter
Description : If temperature change is 19°C, what amount of change to sound velocity is possible? A. 11.53 ft/s B. 11.53 m/s C. 19.304 ft/s D. 19.304 m/s
Last Answer : B. 11.53 m/s
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 : Assume a frequency of 4 MHz, determine the phase shift offered by the line in the above problem. A. 108.5˚ B. 106.5˚ C. 115.5˚ D. 166.5˚
Last Answer : D. 166.5˚
Description : What is the spectrum of stereophonic FM signal? A. 19 to 38 kHz B. 30 to 53 kHz C. 59.5 to 74.5 kHz D. 88 to 108 MHz
Last Answer : B. 30 to 53 kHz
Description : What is the typical separation between the two conductors in a parallel wire line? A. 0.001 to 0.01 m B. 200 to 500 mm C. 0.635 to 15.24 cm D. 2.5 to 5 in.
Last Answer : C. 0.635 to 15.24 cm
Description : Industrial noise frequency is between _____. A. 0 to 10 KHz B. 160 MHz to 200 MHz C. 15 to 160 MHz D. 200 to 3000 MHz
Last Answer : C. 15 to 160 MHz
Description : How far is the visual carrier from the lowest frequency in the spectrum of a monochrome TV broadcast channel following the NTSC standard? A. 1.5 MHz B. 1.25 MHz C. 4.5 MHz D. 0.25 MHz
Last Answer : B. 1.25 MHz
Description : What is the refractive index of an ionospheric layer with 100x105 free electrons per m3 ? Assume frequency to be at 20 MHz. A. 0.99 B. 0.15 C. 0.78 D. 0.85
Last Answer : A. 0.99
Description : Determine the lower half-power frequency of a class-C amplifier having upper half-power frequency of 10.025 MHz, a resonant frequency 5 MHz and a circuit Q of 10. A. 1.0025 MHz B. 10.525 MHz C. 0.5 MHz D. 10 MHz
Last Answer : A. 1.0025 MHz
Description : Industrial noise frequency is between _________. A. 200 to 3000 Mhz B. 15 to 160 Mhz C. 0 to 10 Khz D. 20 Ghz
Last Answer : B. 15 to 160 Mhz
Description : What is actual length in feet of a one-half wavelength of a coax with a velocity factor of 0.59 at 26 MHz? A. 11.16 B. 40.29 C. 42.46 D. 46.28
Last Answer : A. 11.16
Description : What is the actual length in feet of a one-half wavelength of a coax with a velocity factor of 0.63 at 28 MHz? A. 44.28 B. 43.46 C. 11.07 D. 46.27
Last Answer : C. 11.07
Description : Coaxial lines are used on those systems operating _______. A. Below 2 GHz B. At 300 MHz C. Above 10KHz D. Above 10GHz
Last Answer : A. Below 2 GHz
Description : Space diversity transmission means transmitting and receiving on _______. A. Two or more antennas operating on two different frequencies B. Two or more identical frequencies C. Two or more antennas operating on the same frequency D. Two or more different frequency
Last Answer : C. Two or more antennas operating on the same frequency
Description : When the elevation angle of a geostationary satellite is 23˚ and the transmitting frequency is 3840 MHz, what is the free space loss in dB? A. 196 dB B. 200 dB C. 150 dB D. 100 dB
Last Answer : A. 196 dB
Description : Most satellites operate in which frequency band? A. 30 to 300 MHz B. 300 MHz to 3 GHz C. 3 GHz to 30 GHz D. Above 300 GHz
Last Answer : C. 3 GHz to 30 GHz
Description : The bandwidth of C-band satellite frequency band in U.S. A. 500 GHz B. 1000 GHz C. 1000 MHz D. 500 MHz
Last Answer : D. 500 MHz
Description : What is the local oscillator (mixer) frequency of the satellite with an uplink frequency in GHz band? A. 3500 MHz B. 4500 MHz C. 2225 MHz D. 2555 MHz
Last Answer : C. 2225 MHz
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 : What is the most commonly used intermediate frequency of radar receivers? A. 40 MHz B. 60 MHz C. 70 MHz D. 30 MHz
Last Answer : D. 30 MHz
Description : What is the channel number of an FM station with a carrier frequency of 99.5 MHz? A. 256 B. 258 C. 257 D. 259
Last Answer : B. 258
Description : Which of the following systems uses frequency band 870-885 MHz as a transmit band of its base station? A. TACS B. NTT C. NMT D. AMPS
Last Answer : B. NTT
Description : What ionospheric layer has a daytime approximate critical frequency of 8 MHz? A. F2 layer B. F1 layer C. E layer D. D layer
Last Answer : A. F2 layer
Description : What is the approximate critical frequency of the E layer? A. 4 MHz B. 5 MHz C. 6 MHz D. 3 MHz
Last Answer : A. 4 MHz
Description : A radio communications link is to be established via the ionosphere. The maximum virtual height of the layer is 100 km at the midpoint of the path and the critical frequency is 2 MHz. The distance between stations is 600 ... optimum working frequency? A. 6.32 MHz B. 2.1 MHz C. 5.4 MHz D. 1.8 MHz
Last Answer : C. 5.4 MHz
Description : An FM receiver whose intermediate frequency is 10.7 MHz, is experiencing image channel interference from a station transmitting on 121.1 MHz. If the local oscillator is tracking above, the receiver is tuned to A. 131.8 MHz B. 110.4 MHz C. 142.5 MHz D. 99.7 MHz
Last Answer : D. 99.7 MHz
Description : What is the frequency range of an aircraft’s Very High Frequency (VHF) communications? A. 118.000 MHz to 136.975 MHz (worldwide up to 151.975 MHz) B. 108.000 MHz to 117.95 MHz C. 329.15 MHz to 335.00 MHz D. 2.0000 MHz to 29.999 MHz
Last Answer : A. 118.000 MHz to 136.975 MHz (worldwide up to 151.975 MHz)
Description : What is the frequency range of an aircraft’s radio altimeter? A. 962 MHz to 1213 MHz B. 329.15 MHz to 335.00 MHz C. 4250 MHz to 4350 MHz D. 108.00 MHz to 117.95 MHz
Last Answer : C. 4250 MHz to 4350 MHz
Description : Tropospheric scatter is a method of sky wave propagation for which of the following frequency bands? A. 300 kHz to 3 MHz B. 3 MHz to 30 MHz C. 30 MHz to 300 MHz D. 300 MHz to 3 GHz
Last Answer : D. 300 MHz to 3 GHz
Description : Which of the following frequency bands is best suited for sky wave propagation? A. 30 to 300 kHz B. 3 MHz to 30 MHz C. 30 MHz to 300 MHz D. 3 GHz to 30 GHz
Last Answer : B. 3 MHz to 30 MHz
Description : Which of the following frequency bands is best suited for ground wave propagation? A. 30 to 300 kHz B. 300 kHz to 3 MHz C. 3 MHz to 30 MHz D. 30 MHz to 300 MHz
Last Answer : A. 30 to 300 kHz
Description : What is the frequency of a 2-cm sound wave in sea water at 25˚C? A. 76 kHz B. 76 Hz C. 76 MHz D. 76 mHz
Last Answer : A. 76 kHz
Description : What is the typical center frequency spacing between adjacent channels (transponders) in satellites? A. 36 MHz B. 40 MHz C. 500 MHz D. 4 MHz
Last Answer : B. 40 MHz