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 : 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 : A voice-grade circuit using the PTN has an ideal passband of A. 0 to 4 Hz B. 0 to 4 kHz C. 0 to 4 GHz D. 0 to 4 MHz
Last Answer : B. 0 to 4 kHz
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 : Assuming a UHF frequency range of 405.0125 MHz to 405.0875 MHz at 25 kHz channeling plan, how many channels can you produce? A. 2.5 ch. B. 2 ch. C. 4 ch. D. 3 ch.
Last Answer : D. 3 ch.
Description : Assume a frequency range of 405.0125 MHz to 405.0875 MHz and 25 kHz channeling plan, determine the center frequency of the second channel from the lower limit. A. 405.030 MHz B. 405.025 MHz C. 405.050 MHz D. 405.075 MHz
Last Answer : C. 405.050 MHz
Description : Assume a frequency range of 401.000 MHz to 401.050 MHz, if you apply 25 kHz channeling plan, determine the center frequency of the first channel from the lower limit. A. 401.010 MHz B. 401.0125 MHz C. 401.025 MHz D. 401.00625 MHz
Last Answer : B. 401.0125 MHz
Description : The extremely high frequency (EHF) band is in the radio spectrum range of _______. A. 30 to 300 kHz B. 30 to 300 GHz C. 3 to 30 MHz D. 3 to 30 GHz
Last Answer : B. 30 to 300 GHz
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 : In acoustics, if the volume of the room is 200 m3 then at what frequency the coefficient of absorption is measured? A. 120 kHz B. 120 Hz C. 100 Hz D. 150 Hz
Last Answer : B. 120 Hz
Description : What is the typical frequency used for communicating to submerged submarines? A. 100 Hz B. 500 Hz C. 4 kHz D. 200 Hz
Last Answer : A. 100 Hz
Description : What frequency is 10 octaves above 30 Hz? A. 30.72 kHz B. 30 kHz C. 300 Hz D. 307.2 kHz
Last Answer : A. 30.72 kHz
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 : A periodic signal completes onecycle in 0.001 s. What is thefrequency? A) 1 Hz B) 100 Hz C) 1 KHz D) 1 MHz
Last Answer : 1 KHz
Description : Atmospheric noise becomes less severe at frequencies A. above 30 MHz B. below 30 MHz C. above 3000 kHz D. below 3000kHz
Last Answer : A. above 30 MHz
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 : The band of frequencies least susceptible to atmospheric noise and interference is: A. 30 – 300 kHz B. 300 – 3000 kHz C. 3 – 30 MHz D. 300 – 3000 MHz
Last Answer : D. 300 – 3000 MHz
Description : How many voice signals (4 kHz max.) would fit into a 5 MHz spectrum? A. 1250 B. 500 C. 1000 D. 1500
Last Answer : A. 1250
Description : What is the channel spacing for SITOR frequencies? A. 500 Hz B. 170 Hz C. 300 Hz D. 3 kHz
Last Answer : A. 500 Hz
Description : What is the channel spacing for MF-HF voice frequencies? A. 2.8 kHz B. 500 Hz C. 3.5 kHz D. 3 kHz
Last Answer : D. 3 kHz
Description : What is the channel bandwidth of a standard analogue telephone system? A. 300-500 Hz B. 1200 kHz C. 100-300 Hz D. 300-3400 Hz
Last Answer : D. 300-3400 Hz
Description : What is the photon energy for an infrared wave with frequency of 1012 Hz? a. 10.6 x 1034 joules b. 6.63 x 10-34 joules c. 6.63 x 10-22 joules d. 10.6 x 1022 joules
Last Answer : c. 6.63 x 10-22 joules
Description : The midrange frequency range of sound is from A. 256 to 2048 Hz B. 2048 to 4096 Hz C. 512 to 2048 Hz D. 16 to 64 Hz
Last Answer : A. 256 to 2048 Hz
Description : What frequency range is used for FM radio transmission? A. Very Low Frequency : 3 kHz to 30. kHz B. Low Frequency :30 kHz to 300 kHz C. High Frequency :3 MHz to 30 MHz D. Very High Frequency : 30 MHz to 300 MHz E. None of the above
Last Answer : Very High Frequency : 30 MHz to 300 MHz
Description : A typical DME frequency is: a. 1000 MHz b. 1300 MHz c. 1000 kHz d. 1575 MHz
Last Answer : a. 1000 MHz
Description : If the clock frequency to the circuit shown in the illustration were 2 kHz, what would be indicated at the output of 'FF-C'? EL-0087 A. 250 Hz B. 666 Hz C. 6 kHz D. 16 kHz
Last Answer : Answer: A
Description : The frequency-response specification of your tape recorder reads within +/ - 3 dB from 150 Hz to 150 kHz at 60 ips. What does this mean?
Last Answer : The recorder can record all frequencies between 150 Hz and 150 kHz at 60 ips without varying the output amplitude more than 3 dB.
Description : Human ear is most sensitive to noise in the following frequency ranges: (A) 1-2 KHz (B) 100-500 Hz (C) 10-12 KHz (D) 13-16 KHz
Last Answer : (A) 1-2 KHz
Description : What is the wavelength of a signal at 500 MHz? A. 0.062 cm B. 6 meters C. 60 cm D. 60 meters
Last Answer : C. 60 cm
Description : A Hertz antenna is operating on a frequency of 2182 kHz and consists of a horizontal wire that is hanged between two towers. What is the frequency of its third harmonic? A. 727 kHz B. 6546 kHz C. 436 kHz D. 6.546 kHz
Last Answer : B. 6546 kHz
Description : An amplifier operating over the frequency range of 455 to 460 kHz has a 200 kΩ input resistor. What is the RMS noise voltage at the input to this amplifier if the ambient temperature is 17˚C ? A. 40 µV B. 4.0 µV C. 400 µV
Last Answer : B. 4.0 µV
Description : What is the approximate bandwidth of an FM system with 10 kHz of modulating frequency and a 150 kHz of frequency deviation? A. 300 kHz B. 320 kHz C. 150 kHz D. 200 kHz
Last Answer : B. 320 kHz
Description : What is the carrier frequency of supergroup 10? A. 2724 kHz B. 2356 kHz C. 2108 kHz D. 3100 kHz
Last Answer : D. 3100 kHz
Description : A superhet receiver has an IF of 455 kHz and is experiencing image-channel interference on a frequency of 1570 kHz. The receiver is tuned to A. 1115 kHz B. 660 kHz C. 2025 kHz D. 910 kHz
Last Answer : B. 660 kHz
Description : What is the deviation ratio for an FM-phone signal having a maximum frequency swing of plus or minus 5 kHz and accepting a maximum modulation rate of 3kHz? A. 60 B. 0.16 C. 0.6 D. 1.66
Last Answer : D. 1.66
Description : If frequency range of 401.000MHz to 401.050MHz has to be channelized at 12.5 kHz between channel, what is the center of its first channel from the lower limit? A. 401.125MHz B. 401.00625MHz C. 401.025MHz D. 401.0125MHz
Last Answer : B. 401.00625MHz
Description : For a sample rate of 40 kHz, determine the maximum analog input frequency A. 30 kHz B. 40 kHz C. 20 kHz D. 10 kHz
Last Answer : C. 20 kHz
Description : What is the local oscillator frequency range commercial AM broadcast if it is equal to 455 KHz. A. 540 to 1600 KHz B. 0 to 1600 KHz C. 995 to 2055 KHz D. 0 to 455 KHz
Last Answer : C. 995 to 2055 KHz
Description : What is the baseband frequency of standard FDM basic supergroup? A. 312 to 552 kHz B. 300 to 600 kHz C. 60 to 2540 kHz D. 60 to 108 kHz
Last Answer : A. 312 to 552 kHz
Description : The frequency spectrum of the stereophonic FM signal. A. 67 kHz B. 59.5 to 74.5 kHz C. 19 to 38 kHz D. 30 to 53 kHz
Last Answer : D. 30 to 53 kHz
Description : What does the noise weighting curve shows? A. Noise signals measured with a 144 handset B. Power levels of noise found in carrier systems C. The interfering effect of other frequencies in a voice ... a reference frequency of one kilohertz D. Interfering effects of signals compared with a 3-kHz tone
Last Answer : C. The interfering effect of other frequencies in a voice channel compared with a reference frequency of one kilohertz
Description : ECE Board Exam March 1996 What is the purpose of a beat frequency oscillator (BFO)? A. Aid in the reception of weak voice-modulated signals B. Generates a signal, whose frequency is the ... reception D. Generates an output, whose frequency differs from that of the intermediate frequency by 1 kHz
Last Answer : C. Generates a 1kHz note for Morse code reception
Description : If the phase difference between two points is 120° for a wave with velocity of 360 m/ and frequency 500 Hz, then path difference between the two points is – (1) 1 cm (2) 6 cm (3) 12 cm (4) 24 cm
Last Answer : (4) 24 cm
Description : If the phase difference between two points is 120° for a wave with velocity of 360 m/ and frequency 500 Hz, then path difference between the two points is (1) 1 cm (2) 6 cm (3) 12 cm (4) 24 cm
Last Answer : 24 cm
Description : Six (6) MHz crystal oscillator has a stability of 1 part in 106. The largest frequency error expected of this crystals A) 0.06 Hz B) 0.6 Hz C) 6 Hz D) 60 Hz.
Last Answer : C) 6 Hz
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 : 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